pages*: add backticks to every io stream

[ghost]

Similar to PR: #10436

stdin → `stdin`
stdout → `stdout`
stderr → `stderr`

• The page(s) follow the content guidelines.
• The PR title conforms to the recommended templates.

[tldr-bot]

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

pages/common/supervisorctl.md:
Error: Parse error on line 17:
... {{{process_name}} `stderr``- Keep dis
-----------------------^
Expecting 'NEWLINE', 'TEXT', 'DASH', 'BACKTICK', got 'COMMAND_TEXT'
pages/common/textql.md:
Error: Parse error on line 20:
... "{{{SELECT * FROM `stdin`}}"`- Join t
-----------------------^
Expecting 'NEWLINE', 'TEXT', 'DASH', 'BACKTICK', got 'COMMAND_TEXT'

Please fix the error(s) and push again.

[tldr-bot]

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

pages/common/textql.md:
Error: Parse error on line 20:
... "{{{SELECT * FROM `stdin`}}"`- Join t
-----------------------^
Expecting 'NEWLINE', 'TEXT', 'DASH', 'BACKTICK', got 'COMMAND_TEXT'

Please fix the error(s) and push again.

[kbdharun]

LGTM, Thanks for your contribution.