FileCheck: add page

[P2Tree]

• The page(s) are in the correct platform directories: common, linux, osx, windows, sunos, android, etc.
• The page(s) have at most 8 examples.
• The page description(s) have links to documentation or a homepage.
• The page(s) follow the content guidelines.
• The page(s) follow the style guide.
• The PR title conforms to the recommended templates.
• Version of the command being documented (if known):

[tldr-bot]

The build for this PR failed with the following error(s):

pages/common/FileCheck.md:
Error: Parse error on line 5:
...uide/FileCheck.html>- Match `input_fil
-----------------------^
Expecting 'END_INFORMATION_LINK_URL', got 'NEWLINE'
pages/common/FileCheck.md:5: TLDR011 Page never contains more than a single empty line
pages/common/FileCheck.md:0: TLDR109 File name should be lowercase

Please fix the error(s) and push again.

[gutjuri]

Thanks, I have two comments