add max_length to form field type
fix typo in previous commit
fix typo in previous commit
fix last typo on max length option
bug #3432 [Reference][Form Types] Add "max_length" option in form type (nykopol)

This PR was merged into the 2.3 branch.

Discussion
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[Reference][Form Types] Add "max_length" option in form type

| Q             | A
| ------------- | ---
| Doc fix?      | yes
| New docs?     | yes
| Applies to    | 2.3+
| Fixed tickets | #3410 (task Form -> max_length)

Commits
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b53a227 fix last typo on max length option
d6800d3 fix typo in previous commit
391fe30 fix typo in previous commit
2156545 add max_length to form field type