Relax matplotlib constraints

[forsyth2]

Summary

Objectives:
-Relax matplotlib constraints

Issue resolution:

• Closes Update matplotlib constrain to support 3.10.6 #37

Select one: This pull request is...

• a bug fix: increment the patch version
• a small improvement: increment the minor version
• a new feature: increment the minor version
• an incompatible (non-backwards compatible) API change: increment the major version

Small Change

• To merge, I will use "Squash and merge". That is, this change should be a single commit.
• Logic: I have visually inspected the entire pull request myself.
• Pre-commit checks: All the pre-commits checks have passed.

[forsyth2]

@andrewdnolan All checks pass, merging.

[xylar]

@forsyth2, only the upper bound should have been removed here, not the lower bound. That lower bound was put on for a good reason at some point and I presume that reason hasn't gone away.

[forsyth2]

I will make a conda-fixes PR for this as well as the issues noted at #25 (comment).

[xylar]

I got that as well already in #42