build(deps): bump flat and @open-wc/testing

[dependabot[bot]]

Removes flat. It's no longer used after updating ancestor dependency @open-wc/testing. These dependencies need to be updated together.

Removes flat

Updates @open-wc/testing from 2.5.33 to 3.1.7

Release notes

Sourced from @​open-wc/testing's releases.

@​open-wc/testing@​3.1.7

Patch Changes

• b187c0bc: Add types export for node16 module resolution
• Updated dependencies [b187c0bc]
  • @​open-wc/testing-helpers@​2.1.4

@​open-wc/testing@​3.1.6

Patch Changes

• 735b0092: Avoid saving unchanged snapshots
• Updated dependencies [735b0092]
  • @​open-wc/semantic-dom-diff@​0.19.7

@​open-wc/testing@​3.1.5

Patch Changes

• ae9fe3e7: upgrade to chai-dom v1.11.0

@​open-wc/testing@​3.1.4

Patch Changes

• 19b951b6: update semantic-dom-diff dependency

@​open-wc/testing@​3.1.3

Patch Changes

• 48a853fa: Fix deps issues with @​esm-bundle/chai

@​open-wc/testing@​3.1.2

Patch Changes

• 773e5b65: fix: add a type for lit v1 renderable
• Updated dependencies [773e5b65]
  • @​open-wc/testing-helpers@​2.1.2

@​open-wc/testing@​3.1.1

Patch Changes

• ebbea0d5: Force lit-html dependency tree for correct types construction
• Updated dependencies [ebbea0d5]
  • @​open-wc/testing-helpers@​2.1.1

@​open-wc/testing@​3.1.0

Minor Changes

• b762707d: Feat/customize render

Patch Changes

... (truncated)

Changelog

Sourced from @​open-wc/testing's changelog.

3.1.7

Patch Changes

• b187c0bc: Add types export for node16 module resolution
• Updated dependencies [b187c0bc]
  • @​open-wc/testing-helpers@​2.1.4

3.1.6

Patch Changes

• 735b0092: Avoid saving unchanged snapshots
• Updated dependencies [735b0092]
  • @​open-wc/semantic-dom-diff@​0.19.7

3.1.5

Patch Changes

• ae9fe3e7: upgrade to chai-dom v1.11.0

3.1.4

Patch Changes

• 19b951b6: update semantic-dom-diff dependency

3.1.3

Patch Changes

• 48a853fa: Fix deps issues with @​esm-bundle/chai

3.1.2

Patch Changes

• 773e5b65: fix: add a type for lit v1 renderable
• Updated dependencies [773e5b65]
  • @​open-wc/testing-helpers@​2.1.2

3.1.1

Patch Changes

• ebbea0d5: Force lit-html dependency tree for correct types construction
• Updated dependencies [ebbea0d5]
  • @​open-wc/testing-helpers@​2.1.1

... (truncated)

Commits

• 0182490 Version Packages (#2508)
• b187c0b Add types export to testing & testing-helpers (#2507)
• bb6488c Version Packages
• 2bbdef9 Version Packages
• ae9fe3e chore(testing): upgrade chai-dom and its types
• 35894ab Version Packages
• 19b951b chore(testing): bump semantic dom diff
• 8690d36 Version Packages
• b9271ee fix(testing): chai dependency uses correct imports
• da1d3d9 Version Packages (#2417)
• Additional commits viewable in compare view

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