Bump marshmallow from 3.9.0 to 3.12.1

Bumps marshmallow from 3.9.0 to 3.12.1.

Changelog

Sourced from marshmallow's changelog.

3.12.1 (2021-05-10)

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Bug fixes:

• Fix bug that raised an AttributeError when instantiating a Schema with a field named parent (:issue:1808). Thanks :user:flying-sheep for reporting and helping with the fix.

3.12.0 (2021-05-09)

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Features:

• Add validate.And (:issue:1768). Thanks :user:rugleb for the suggestion.
• Add type annotations to marshmallow.decorators (:issue:1788, 🇵🇷1789). Thanks :user:michaeldimchuk for the PR.
• Let Field\s be accessed by name as Schema attributes (🇵🇷1631).

Other changes:

• Improve types in marshmallow.validate (🇵🇷1786).
• Make marshmallow.validate.Validator an abstract base class (🇵🇷1786).
• Remove unnecessary list cast (🇵🇷1785).

3.11.1 (2021-03-29)

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Bug fixes:

• Fix treatment of dotted keys when unknown=INCLUDE (:issue:1506). Thanks :user:rbu for reporting and thanks :user:sirosen for the fix (🇵🇷1745).

3.11.0 (2021-03-28)

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Features:

• Add fields.IPInterface, fields.IPv4Interface, and IPv6Interface (:issue:1733). Thanks :user:madeinoz67 for the suggestion and the PR.
• Raise AttributeError for missing methods when using fields.Method (🇵🇷1675). Thanks :user:lassandroan.

Other changes:

• Remove unnecessary hasattr and getattr checks in Field (🇵🇷1770).

3.10.0 (2020-12-19)

... (truncated)

Commits

• 6522565 Bump version and update changelog
• dbfc747 Bind the root schema to the field to avoid the parent attribute being overwri...
• 23d0551 Bump flake8 from 3.9.1 to 3.9.2
• 6927021 Bump sphinx from 3.5.4 to 4.0.0 (#1807)
• b10bf47 Bump autodocsumm from 0.2.3 to 0.2.4 (#1805)
• ecf6930 Bump version and update changelog
• 721976d Type hinted all the decorators in marshmallow/decorators.py (#1789)
• 4041fb4 Fix markup of code literals in changelog (#1804)
• 199e185 Upgrade to GitHub-native Dependabot (#1800)
• 97f8375 Fix Url and Email fields docstrings
• Additional commits viewable in compare view