Update symfony/yaml requirement from ^6.0 to ^7.1

[dependabot]

Updates the requirements on symfony/yaml to permit the latest version.

Release notes

Sourced from symfony/yaml's releases.

v7.1.1

Changelog (symfony/yaml@v7.1.0...v7.1.1)

• no significant changes

Changelog

Sourced from symfony/yaml's changelog.

CHANGELOG

7.1

• Add support for getting all the enum cases with !php/enum Foo

7.0

• Remove the !php/const: tag, use !php/const instead (without the colon)

6.3

• Add support to dump int keys as strings by using the Yaml::DUMP_NUMERIC_KEY_AS_STRING flag

6.2

• Add support for !php/enum and !php/enum *->value
• Deprecate the !php/const: tag in key which will be replaced by the !php/const tag (without the colon) since 3.4

6.1

• In cases where it will likely improve readability, strings containing single quotes will be double-quoted

5.4

• Add new lint:yaml dirname --exclude=/dirname/foo.yaml --exclude=/dirname/bar.yaml option to exclude one or more specific files from multiple file list
• Allow negatable for the parse tags option with --no-parse-tags

5.3

• Added github format support & autodetection to render errors as annotations when running the YAML linter command in a Github Action environment.

5.1.0

• Added support for parsing numbers prefixed with 0o as octal numbers.

• Deprecated support for parsing numbers starting with 0 as octal numbers. They will be parsed as strings as of Symfony 6.0. Prefix numbers with 0o so that they are parsed as octal numbers.

  Before:

... (truncated)

Commits

• fa34c77 Merge branch '7.0' into 7.1
• 89bdddd Merge branch '6.4' into 7.0
• 52903de Merge branch '5.4' into 6.4
• 81cad0c Revert "minor #54653 Auto-close PRs on subtree-splits (nicolas-grekas)"
• c5f718c Merge branch '7.0' into 7.1
• 0d3916a Merge branch '6.4' into 7.0
• 53e8b1e Merge branch '5.4' into 6.4
• bc780e1 call substr() with integer offsets
• c1e0024 Merge branch '7.0' into 7.1
• cbe25f6 Merge branch '6.4' into 7.0
• Additional commits viewable in compare view

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