Add change log entries from patch releases

[palas]

Changelog

- description: |
    Add change log entries from patch release
  type:
    - maintenance    # not directly related to the code
  projects:
    - cardano-api

Context

We have back-ported these two bug-fixes:

• Fix canonical CBOR bug #1047
• Remove duplicated orphans and re-import testlibs #1051

Because versions patched have diverged from master and also have the same changes in different parts of the commit history, it doesn't make sense to merge the patch release PRs to master. But because we don't do that, the change log entries for those releases are also not in the CHANGELOG.md file in master.

This PR fixes that, by adding the change log entries from the patch releases to the master branch.

How to trust this PR

The contents are just copied from the release PRs for patches. These are the relevant PRs:

• Release cardano-api-10.13.2.0 #1053
• Release cardano-api-10.14.2.0 #1061
• Release cardano-api-10.15.1.0 #1062
• Release cardano-api-10.16.4.0 #1063
• Release cardano-api-10.17.3.0 #1064
• Release cardano-api-10.18.1.0 #1065
• Release cardano-api-10.19.2.0 #1066
• Release cardano-api-10.20.1.0 #1067

Checklist

• Commit sequence broadly makes sense and commits have useful messages
• New tests are added if needed and existing tests are updated. See Running tests for more details
• Self-reviewed the diff