issue 12664
minor #12673 [Form] [Hackday] [2.7] Add a deprecation note about the `form_enctype` helper (mrcmorales)

This PR was merged into the 2.7 branch.

Discussion
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[Form] [Hackday] [2.7] Add a deprecation note about the `form_enctype` helper

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | no
| BC breaks?    | no
| Deprecations? | yes
| Tests pass?   | yes
| Fixed tickets | #12664
| License       | MIT
| Doc PR        |

Commits
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2061a88 issue 12664