Drop support for model_timezone and view_timezone options in TimeType and DateType.
feature #12404 [Form] Remove timezone options from DateType and TimeType (jakzal)

This PR was submitted for the master branch but it was merged into the 2.6 branch instead (closes #12404).

Discussion
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[Form] Remove timezone options from DateType and TimeType

| Q             | A
| ------------- | ---
| Bug fix?      | yes
| New feature?  | no
| BC breaks?    | yes
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #12239
| License       | MIT
| Doc PR        | https://github.com/symfony/symfony-docs/pull/4417

replaces #12380

Commits
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849fb29 Drop support for model_timezone and view_timezone options in TimeType and DateType.