Bump marshmallow from 2.18.1 to 3.12.1

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Bumps marshmallow from 2.18.1 to 3.12.1.

Changelog

Sourced from marshmallow's changelog.

3.12.1 (2021-05-10)

Bug fixes:

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

3.12.0 (2021-05-09)

Features:

• Add validate.And (1768). Thanks rugleb for the suggestion.
• Add type annotations to marshmallow.decorators (1788, 1789). Thanks michaeldimchuk for the PR.
• Let Fields 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)

Bug fixes:

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

3.11.0 (2021-03-28)

Features:

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

Other changes:

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

3.10.0 (2020-12-19)

Deprecations:

• Passing field metadata via keyword arguments is deprecated and will be removed in marshmallow 4 (1350). Use the explicit metadata=... argument instead. Thanks sirosen.

3.9.1 (2020-11-07)

... (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

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