minor symfony#59105 [FrameworkBundle] Rename TranslationUpdateCommand to TranslationExtract command to match the command name (welcoMattic)

This PR was merged into the 7.3 branch.

Discussion
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[FrameworkBundle] Rename TranslationUpdateCommand to TranslationExtract command to match the command name

| Q             | A
| ------------- | ---
| Branch?       | 7.3 <!-- see below -->
| Bug fix?      | no
| New feature?  | no <!-- please update src/**/CHANGELOG.md files -->
| Deprecations? | yes <!-- please update UPGRADE-*.md and src/**/CHANGELOG.md files -->
| Issues        | Fix #... <!-- prefix each issue number with "Fix #", no need to create an issue if none exists, explain below instead -->
| License       | MIT

In symfony#43758, `translation:update` command has been renamed to `translation:extract` command. But the file has never been renamed. This PR deprecate the `TranslationUpdateCommand` class in favor to `TranslationExtractCommand`. So, in 8.0 we could remove `TranslationUpdateCommand` file completely.

Commits
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a61bd89 Rename TranslationUpdateCommand to TranslationExtract command to match the command name

Author: fabpot

src/Symfony/Bundle/FrameworkBundle/CHANGELOG.md

@@ -5,6 +5,7 @@ CHANGELOG
 ---
 
  * Add support for assets pre-compression
+ * Rename `TranslationUpdateCommand` to `TranslationExtractCommand`
 
 7.2
 ---