chore(deps-dev): bump vnu-jar from 20.6.30 to 21.2.5

[dependabot[bot]]

Bumps vnu-jar from 20.6.30 to 21.2.5.

Changelog

Sourced from vnu-jar's changelog.

With a few exceptions, this is a record of mainly just user-facing changes — that is, either changes to the actual behavior of the checker, or changes to any options/interfaces the checker exposes for developers.

NN.NN.NN

NN XXX NNNN

• Allow loading attribute for the iframe element (lazy loading)
• Allow autocomplete=username with input[type=email]
• Allow more values for SVG feBlend element mode attribute
• CLI: Add nu.validator.htmlparser.tools|test classes to vnu.jar
• CLI/Docker: Enable setting timeouts & bind address w/ environment vars
• CSS: Support color-adjust
• Docker: Migrate Dockerfile to “distroless” image (reduces image size)
• ARIA: Allow aria-required with input[type=file]
• Update doc-fetching backend to Apache HTTP Components HttpClient 4.5.9
• Make the checker use HTTP 1.0 for all requests it make, not HTTP 1.1
• Make the checker ignore error for malformed/missing HTTP closing chunk

Commits

• 2710079 Travis CI: Add openjdk16 to the build matrix
• f40299c Allow more values for SVG feBlend "mode" attribute
• 270d48a Allow autocomplete="username" w/ input[type=email]
• 6a41cff Experimentally make checker use HTTP 1.0, not 1.1
• 082d29e chore: Run git add --renormalize .
• 1c05d38 chore: create issue templates
• ab7acd2 Allow "loading" attr for "iframe" (lazy loading)
• 4512418 fix: Remove leading space for Style "type" message
• 2e26a23 Update tests
• fe147dd Gather (anonymized) stats on errors and warnings
• Additional commits viewable in compare view

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