feature #57518 Unify how --format is handled by commands (fabpot)

This PR was merged into the 7.2 branch.

Discussion
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Unify how --format is handled by commands

| Q             | A
| ------------- | ---
| Branch?       | 7.2
| Bug fix?      | no
| New feature?  | yes <!-- please update src/**/CHANGELOG.md files -->
| Deprecations? | yes <!-- please update UPGRADE-*.md and src/**/CHANGELOG.md files -->
| Issues        | n/a <!-- prefix each issue number with "Fix #", no need to create an issue if none exists, explain below instead -->
| License       | MIT

We have many commands that have a `--format` option. This PR tries to unify the way we handle them:

* Deprecate the `text` format (used only twice) in favor of the more common `txt` one;
* Add auto-completion for `--format` in all commands;
* Add help about the `--format` option in all commands that supports it (in a unified way)

**Side note**: To avoid confusion, I think we should rename the `--format` option for the `uuid:generate` and `ulid:generate` commands as it does something different from the commonly used `--format` option.

Commits
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848f855cdf Unify how --format is handle by commands

Author: fabpot

Command/LintCommand.php

@@ -72,6 +72,9 @@ protected function configure(): void
 Or of a whole directory:
 
   <info>php %command.full_name% dirname</info>
+
+The <info>--format</info> option specifies the format of the command output:
+
   <info>php %command.full_name% dirname --format=json</info>
 
 You can also exclude one or more specific files:
@@ -266,6 +269,7 @@ public function complete(CompletionInput $input, CompletionSuggestions $suggesti
         }
     }
 
+    /** @return string[] */
     private function getAvailableFormatOptions(): array
     {
         return ['txt', 'json', 'github'];