[WIP][Valiadtor] - EmailConstraint reference
Use of Sphinx markup
Version added and clarifications
Link moved and heading updated
Typo and link label
Lowercase and link label
CS
Blank line restored
feature #3469 [Validator] - EmailConstraint reference (egulias)

This PR was merged into the master branch.

Discussion
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[Validator] - EmailConstraint reference

| Q             | A
| ------------- | ---
| Doc fix?      | no
| New docs?     | yes - https://github.com/symfony/symfony/pull/9140
| Applies to    | master
| Fixed tickets |

Note
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I'm not sure if this behaviour change should go in a page by itself (like https://github.com/symfony/symfony-docs/blob/2.4/components/dependency_injection/lazy_services.rst) since requires the installation of an external library to work.
I appreciate some guide on this since it's my first doc PR, thanks.

Commits
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257c483 Blank line restored
c50f041 CS
a0dd460 Lowercase and link label
aa5aa61 Typo and link label
517e4c5 Link moved and heading updated
f0b3b85 Version added and clarifications
e4a0e2f Use of Sphinx markup
faa034b [WIP][Valiadtor] - EmailConstraint reference