Add support for YAML anchors

[moklidia]

We need to be able to parse YAML anchors for a more seamless user experience

https://www.cloudsavvyit.com/10765/how-to-simplify-docker-compose-files-with-yaml-anchors-and-extensions/#:~:text=YAML%20anchors%20are%20a%20feature,the%20value%20following%20the%20anchor.

[zipofar]

MR: #123
Also was changed uffizzi_cli - MR UffizziCloud/uffizzi_cli#108

So if testing with help uffizzi_cli we should use that changes

[NealArw]

TESTED - OK

File: Click to expand

definitions:
    environment: &env-var
      POSTGRES_USER: postgres
      POSTGRES_PASSWORD: postgres

services:
  redis:
    image: redis:latest
    environment: *env-var

  postgres:
    image: postgres:9.6
    secrets:
      - user
      - password
      - neal
    environment: *env-var

  nginx:
    image: nginx:latest
    configs:
      - source: my_config_2
        target: /etc/nginx/conf.d/default.conf

  worker:
    image: uffizzi/example-voting-app-worker:master
    deploy:
      resources:
        limits:
          memory: 250M

  vote:
    image: uffizzi/example-voting-app-vote:master

  result:
    image: uffizzi/example-voting-app-result:master

x-uffizzi-ingress:
  service: nginx
  port: 8080
  
x-uffizzi-continuous_preview:
  deploy_preview_when_pull_request_is_opened: true
  delete_preview_when_pull_request_is_closed: true
  delete_preview_after: 2h
  share_to_github: true
  deploy_preview_when_image_tag_is_created: true
  delete_preview_when_image_tag_is_updated: true
  
configs:
  my_config_2:
    file: ./vote2.conf

secrets:
  user:
    external: true               # indicates value is external to this repository
    name: "POSTGRES_USER"  
  password:
    external: true               # indicates value is external to this repository
    name: "POSTGRES_PASSWORD"
  neal:
    external: true               # indicates value is external to this repository
    name: "TEST_NEAL"  

Result: Click to expand

containers: [{
    : id => 29,
    : kind => "user",
    : image => "library/nginx",
    : tag => "latest",
    : variables => [],
    : secret_variables => nil,
    : created_at => "2022-05-24T14:12:38.505Z",
    : updated_at => "2022-05-24T14:12:42.378Z",
    : memory_limit => 125,
    : memory_request => 125,
    : entrypoint => nil,
    : command => nil,
    : port => 8080,
    : public => true,
    : repo_id => 29,
    : continuously_deploy => "enabled",
    : receive_incoming_requests => true,
    : healthcheck => {}
}, {
    : id => 27,
    : kind => "user",
    : image => "library/redis",
    : tag => "latest",
    : variables => [{
        : name => "POSTGRES_USER",
        : value => "postgres"
    }, {
        : name => "POSTGRES_PASSWORD",
        : value => "postgres"
    }],
    : secret_variables => nil,
    : created_at => "2022-05-24T14:12:38.485Z",
    : updated_at => "2022-05-24T14:12:42.263Z",
    : memory_limit => 125,
    : memory_request => 125,
    : entrypoint => nil,
    : command => nil,
    : port => nil,
    : public => false,
    : repo_id => 27,
    : continuously_deploy => "enabled",
    : receive_incoming_requests => false,
    : healthcheck => {}
}, {
    : id => 28,
    : kind => "user",
    : image => "library/postgres",
    : tag => "9.6",
    : variables => [{
        : name => "POSTGRES_USER",
        : value => "postgres"
    }, {
        : name => "POSTGRES_PASSWORD",
        : value => "postgres"
    }],
    : secret_variables => [{
        : name => "POSTGRES_USER",
        : value => "******"
    }, {
        : name => "POSTGRES_PASSWORD",
        : value => "******"
    }, {
        : name => "TEST_NEAL",
        : value => "******"
    }],
    : created_at => "2022-05-24T14:12:38.493Z",
    : updated_at => "2022-05-24T14:12:42.319Z",
    : memory_limit => 125,
    : memory_request => 125,
    : entrypoint => nil,
    : command => nil,
    : port => nil,
    : public => false,
    : repo_id => 28,
    : continuously_deploy => "enabled",
    : receive_incoming_requests => false,
    : healthcheck => {}
}, {
    : id => 30,
    : kind => "user",
    : image => "uffizzi/example-voting-app-worker",
    : tag => "master",
    : variables => [],
    : secret_variables => nil,
    : created_at => "2022-05-24T14:12:38.516Z",
    : updated_at => "2022-05-24T14:12:42.405Z",
    : memory_limit => 250,
    : memory_request => 250,
    : entrypoint => nil,
    : command => nil,
    : port => nil,
    : public => false,
    : repo_id => 30,
    : continuously_deploy => "enabled",
    : receive_incoming_requests => false,
    : healthcheck => {}
}, {
    : id => 31,
    : kind => "user",
    : image => "uffizzi/example-voting-app-vote",
    : tag => "master",
    : variables => [],
    : secret_variables => nil,
    : created_at => "2022-05-24T14:12:38.525Z",
    : updated_at => "2022-05-24T14:12:42.439Z",
    : memory_limit => 125,
    : memory_request => 125,
    : entrypoint => nil,
    : command => nil,
    : port => nil,
    : public => false,
    : repo_id => 31,
    : continuously_deploy => "enabled",
    : receive_incoming_requests => false,
    : healthcheck => {}
}, {
    : id => 32,
    : kind => "user",
    : image => "uffizzi/example-voting-app-result",
    : tag => "master",
    : variables => [],
    : secret_variables => nil,
    : created_at => "2022-05-24T14:12:38.533Z",
    : updated_at => "2022-05-24T14:12:42.485Z",
    : memory_limit => 125,
    : memory_request => 125,
    : entrypoint => nil,
    : command => nil,
    : port => nil,
    : public => false,
    : repo_id => 32,
    : continuously_deploy => "enabled",
    : receive_incoming_requests => false,
    : healthcheck => {}
}]