fix: Parsing for qualifiers with colon characters

[KDB223]

parseColumnName() uses .split(':') to find the qualifier, but this parses qualifiers with : chars in it incorrectly, since they also are picked up by the split. This causes it to ignore everything after : in the qualifier.

e.g. consider a column name "foo:bar:baz"
parseColumnName() parses this incorrectly as

{
  family: 'foo', 
  qualifier: 'bar'
}

Using slice() instead with the index of the first : character fixes this:

{
  family: 'foo', 
  qualifier: 'bar:baz'
}

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[danieljbruce]

Please fix the tests should array-ify the input and should parse a family name and modify the last commit so that the conventional commits github action passes.

[generated-files-bot]

Warning: This pull request is touching the following templated files:

• .github/workflows/ci.yaml - .github/workflows/ci.yaml (GitHub Actions) should be updated in synthtool

[KDB223]

All done, tested locally. Apologies for the noise.

Changed the qualifier assertion to check for null instead of undefined since we can't return undefined from the method.

[danieljbruce]

I recommend setting qualifier to undefined so that this code works the same way as before when the string doesn't contain a colon.

[KDB223]

I tried that too, however the ParsedColumn interface does not declare undefined as an acceptable type for qualifier at https://github.com/googleapis/nodejs-bigtable/blob/main/src/mutation.ts#L35.

Adding undefined here would solve this:

export interface ParsedColumn {
  family: string | null;
  qualifier: string | null | undefined;
}

[danieljbruce]

Consider adding another test?