Unit Test Fixes

[acwhite211]

Fixes #7662

Fixes the various failing unit tests currently in main. The two groups the unit tests that are fixed in this PR are the tree synonymy and locality update tests.

Checklist

• Self-review the PR after opening it to make sure the changes look good and
  self-explanatory (or properly documented)
• Add relevant issue to release milestone
• Add pr to documentation list

Testing instructions

• See that all the unit tests are passing in the GitHub Actions.

[melton-jason]

I fixed a bug where the backend was completely ignoring the value of the sp7.allow_adding_child_to_synonymized_parent preferences.

The problem is that we were using a regular expression to fetch the value of the Remote Preference (now Collection Preference) prior to 61cc51b (introduced in #7557), and when we transitioned to a JSON dictionary approach to storing the preference, the regular expression was used as the key in the backend to fetch the preference value-- where it should have been using the string literal.

Below is the code from v7.11.3:

specify7/specifyweb/backend/trees/extras.py

Lines 401 to 402 in dcecec6

	pattern = r'^sp7\.allow_adding_child_to_synonymized_parent\.' + node.specify_model.name + '=(.+)'
	override = re.search(pattern, get_remote_prefs(), re.MULTILINE)

Below is the code in main:

specify7/specifyweb/backend/trees/extras.py

Lines 420 to 423 in 6683008

	synonymized = treeManagement_pref.get('synonymized', {}) \
	if isinstance(treeManagement_pref, dict) else {}
	add_synonym_enabled = synonymized.get(r'^sp7\.allow_adding_child_to_synonymized_parent\.' + node.specify_model.name + '=(.+)', False) if isinstance(synonymized, dict) else False

We should be using the literal sp7.allow_adding_child_to_synonymized_parent.TREE string rather than the regular expression as the key.

This fix also simplified some of the other changes in this PR, so feel free to give it a once over @acwhite211!

I'm not going to explicitly approve this PR due to the changes I've made (those should probably be reviewed first), but I'll be down to merge once the additional changes are reviewed further!

[melton-jason]

Love the new helper functions for reading preferences! 🥳

[acwhite211]

There's a front-end issue in main causing lots of failures in the front-end unit testing. It has to do with ajax mocking. I've been looking into a solution, but nothing working yet.

[acwhite211]

I simplified the tree management structure and synonymy changes as to avoid putting too much complexity into this PR. The scope of this PR was starting to get too far away from fixing unit tests related to trees, so these changes are now better scoped to this PR. We can look into doing more structural changes to the tree management data in a future issue.

I was able to fix the failing front-end unit tests related to ajax mocking by making adjustments in the ajax utils index.js file.

@melton-jason ready for re-review.