feat(conventional-commits-parser): add flag to enable/disable multiple-scopes (default: enabled)

[wlc015f]

This PR close to issue 4015

migrate separating scopes logic code from @commitlint/rules/src/scope-enum.ts.

to Implement the feature add isEnableMultipleScopes and scopeDelimitersPattern parserOptions:

• isEnableMultipleScopes used to determine whether to separate scopes by slash or comma delimiters contain in scope.

• scopeDelimitersPattern used to separate scopes if isEnableMultipleScopes value is true.

the two default parserOptions values of two parserOptions refer to @commitlint/rules/src/scope-enum.ts, this pr make it configurable, and work as before if not config

[coveralls]

coverage: 77.026% (+0.1%) from 76.919%
when pulling 752517e on wlc015f:feat/add-flag-whether-to-separate-scope
into 4fec5d3 on conventional-changelog:master.

[knocte]

Why do we need a flag at all? Why not just assume multiple scopes? Do we have a unit test that would fail if this is done without a flag?

[wlc015f]

Why do we need a flag at all? Why not just assume multiple scopes? Do we have a unit test that would fail if this is done without a flag?

our projects previous use scope like: feat(A/B): commit msg, B is a sub scope of A, when we update @commitlint/cli from 8.3.5 to 19.2.1, it doesn't work well as before, because for version 19.2.1 "/" is scopes delimiter to separate input scope string into several scopes. scopeEnum function in @commitlint/rules would separate input scope "A/B" to scope "A" and "B", scope "A/B" can not pass scopeEnum check.

so i want to migrate separating scopes logic code from @commitlint/rules/src/scope-enum.ts to packageconventional-commits-parser, set default behavior work as before in @commitlint/rules, and then set isEnableMultipleScopes=false can solve my problem.