fix: Freezes macaroonbakery

[gruyaume]

Description

The end to end tests are currently failing because of an issue with the new version of macaroonbakery (1.3.3) which is imported by Juju. Here we freeze it to 1.3.2.

TypeError: Descriptors cannot be created directly.
If this call came from a _pb2.py file, your generated code is out of date and must be regenerated with protoc >= 3.19.0.
If you cannot immediately regenerate your protos, some other possible workarounds are:
 1. Downgrade the protobuf package to 3.20.x or lower.
 2. Set PROTOCOL_BUFFERS_PYTHON_IMPLEMENTATION=python (but this will use pure-Python parsing and will be much slower).

Reference

• https://pypi.org/project/macaroonbakery/

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have made corresponding changes to the documentation
• I have added tests that validate the behaviour of the software
• I validated that new and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules
• I have bumped the version of the library

[gatici]

Suggest to insert it into file in alphabetical order.