chore: Add verify code styles workflow.

[filzrev]

This PR add lint workflow to verify code styles.
By executing dotnet format --verify-no-changes command.

If diffs are found.
lint.ymlworkflow add following sticky comment to PR.

## Failed to run the `lint.yml` workflow
To fix workflow errors. Please follow the steps below.
 1. Run `dotnet format` command.
 2. Commit changes as separated commit.
 3. Push changes to source branch of PR.

[filzrev]

Workflow failed with following error.

marocchino/sticky-pull-request-comment@331f8f5b4215f0445d3c07b4967662a32a2d3e31 is not allowed to be used in dotnet/docfx.
Actions in this workflow must be: within a repository that belongs to your Enterprise account, created by GitHub, verified in the GitHub Marketplace,
or matching the following: 

codecov/codecov-action@*,
peaceiris/actions-gh-pages@*, 
azure/pipelines@*, 
khan/pull-request-comment-trigger@*, 
stefanzweifel/git-auto-commit-action@*, 
paulhatch/semantic-version@*, 
dorny/test-reporter@*.

@yufeih
Is it able to add marocchino/sticky-pull-request-comment@* to allowed list?
I thought security risk is relatively low because action is referenced with pinned commit hash.

Alternative solution is to using gh pr comment command.
But it's hard to implement sticky-pull-request-comment like features.

[yufeih]

@filzrev marocchino/sticky-pull-request-comment@* added to allow list

[filzrev]

Following error is thrown when running lint workflow.

Error: Resource not accessible by integration

It seems it can's get permission to write comment when using pull_request trigger
And PR is created from forked repository.
(It need to use pull_request_target trigger instead. but it's not desirable for security reasons)

I need to switch alternative solution instead of sticky-pull-request-comment approach.

[filzrev]

Add commit (f5ef9ab)
to suppress dotnet format --verify-no-changes error that occurred when running on CI (Ubuntu environment).

It seems relating to following issue.

• https://github.com/dotnet/format/issues/1566