[Form] Added support for PATCH requests
merged branch bschussek/issue1341 (PR #7849)

This PR was merged into the master branch.

Discussion
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[Form] Added support for PATCH requests

| Q             | A
| ------------- | ---
| Bug fix?      | no
| New feature?  | yes
| BC breaks?    | no
| Deprecations? | no
| Tests pass?   | yes
| Fixed tickets | #1341
| License       | MIT
| Doc PR        | not needed

Commits
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eabb7a1 [Form] Added support for PATCH requests