feat(ci)!: complete workflows revamp (#1437)

* chore(ci): move spec-file into scripts

* feat(ci)!: rework workflows and build processes

All Python setups route through one local action, and checks are much
more conditional. There is more to be done, but this is a significant
improvement in processing time and redundancy.

As well, nightly builds are made (though not made as GitHub releases..
yet).

* ci: remove symlinked CHANGELONG.md from build_docs.yml paths

* docs: update location of tagstudio.spec

* ci: enforce single quotes in github yaml files

* ci(tests): remove macOS pytest runner

---------

Co-authored-by: Travis Abendshien <46939827+CyanVoxel@users.noreply.github.com>

docs/developing.md

@@ -236,13 +236,13 @@ direnv allow
 To build your own executables of TagStudio, first follow the steps in "[Installing Dependencies](#installing-dependencies)." Once that's complete, run the following PyInstaller command:
 
 ```
-pyinstaller tagstudio.spec
+pyinstaller scripts/tagstudio.spec
 ```
 
 If you're on Windows or Linux and wish to build a portable executable, then pass the following flag:
 
 ```
-pyinstaller tagstudio.spec -- --portable
+pyinstaller scripts/tagstudio.spec -- --portable
 ```
 
 The resulting executable file(s) will be located in a new folder named "dist".