Embed common packages from monorepo

[vearutop]

Description

This PR adds a make common target to copy messages and gherkin packages from common monorepo into godog's internal. This is an alternative solution to migrate away from github.com/cucumber/messages-go and github.com/cucumber/gherkin-go while not depending on a monorepo.

Motivation & context

Once common monorepo has an update in gherkin and/or messages, a godog maintainer can run make common and create a PR with produced changes.

Pros:

• more control for future breaking changes as messages package is not directly importable by end-users
• no runtime dependency on relatively large common monorepo

Cons:

• +10k lines of code in godog repo
• no way for users to import internal/messages in case they need it for advanced step definitions (can be solved by providing more local aliases in godog package)
• manual upgrade procedure for common packages (though it would still be manual when importing common directly)
• embedded code does not pass golint and is excluded from linting (may be fixed in monorepo, but with breraking changes in symbol names)
• overall code coverage drops when merged with embedded packages (can be fixed by improving coverage in monorepo)

Resolves #389.

Type of change

• Refactoring/debt (improvement to code design or tooling without changing behaviour)
• Breaking change (will cause existing functionality to not
  work as expected)

Note to other contributors

No notes.

Update required of cucumber.io/docs

No update.

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

[codecov]

Codecov Report

Merging #428 (ba12413) into main (239a424) will decrease coverage by 41.22%.
The diff coverage is 68.91%.

@@             Coverage Diff             @@
##             main     #428       +/-   ##
===========================================
- Coverage   81.57%   40.34%   -41.23%     
===========================================
  Files          26       37       +11     
  Lines        2176     6233     +4057     
===========================================
+ Hits         1775     2515      +740     
- Misses        308     3559     +3251     
- Partials       93      159       +66     

Impacted Files	Coverage Δ
formatters/fmt.go	100.00% <ø> (ø)
internal/formatters/fmt.go	72.72% <ø> (ø)
internal/formatters/fmt_base.go	86.17% <ø> (ø)
internal/formatters/fmt_cucumber.go	84.76% <ø> (ø)
internal/formatters/fmt_events.go	97.09% <ø> (ø)
internal/formatters/fmt_multi.go	91.66% <ø> (ø)
internal/formatters/fmt_pretty.go	80.56% <ø> (ø)
internal/formatters/fmt_progress.go	93.15% <ø> (ø)
internal/formatters/undefined_snippets_gen.go	41.46% <ø> (ø)
internal/gherkin/dialects_builtin.go	100.00% <ø> (ø)
... and 29 more

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[vearutop]

Closing this, as we need to migrate to different standalone modules (cucumber/common#2029).