chore: markdownlint-cli2-config is removed use --config flag inst…

…ead (#884)

* chore: `markdownlint-cli2-config` is removed use `--config` flag instead

The entry point `markdownlint-cli2-config` was removed in markdownlint-cli2
version 0.12.0.

See https://github.com/DavidAnson/markdownlint-cli2/blob/82c791e94c2e2ab2119437d61c722c8e0c20d6c9/CHANGELOG.md?plain=1#L11-L12

And failed build in https://github.com/nunit/nunit.analyzers/actions/runs/7596383794/job/20690026186?pr=675

* chore: Also satisfy "MD055 - Table pipe style"

The default is "consistent", so the first table defines the format.
And the format is "leading_and_trailing"

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Co-authored-by: Mikkel Bundgaard <[email protected]> a1fff4a