Fix formatting and add missing link in quickstart.md

[AntoniKania]

References

While reading the documentation on GitHub, I came across some pretty weird formatting. It looks like one backtick sign was missing. After looking at .md file, I also found a single ] sign after the word examples, I think that link to https://github.com/wiremock/wiremock-testcontainers-go/blob/main/examples/quickstart/quickstart_test.go should be placed there, so I also added that. If that wasn't intended, please let me know, and I will remove that :)

Screenshots before and after the change:

• before
  
• after
  

Submitter checklist

• The PR request is well described and justified, including the body and the references
• The PR title represents the desired changelog entry
• The repository's code style is followed (see the contributing guide)
• Test coverage that demonstrates that the change works as expected
• For new features, there's necessary documentation in this pull request or in a subsequent PR to wiremock.org

[oleg-nenashev]

Thanks!