When loading, get the config canonical file path

[rafi]

Fix issue when config files are symlinks in ~/.tmuxp.

For example,

$ tree ~/.tmuxp
/Users/bob/.tmuxp
├── hooray-api.yml -> /Users/bob/code/python/hooray/api/.tmuxp.yml
└── hooray-web.yml -> /Users/bob/code/python/hooray/web/.tmuxp.yml

Once loaded, it is expected for /Users/bob/code/python/hooray/... to be the current directory, specially when using start_directory: ./ within the configuration file.
Before this patch, the current directory will improperly resolve to /Users/bob/.tmuxp.

[codecov-io]

Codecov Report

Merging #236 into master will decrease coverage by 0.08%.
The diff coverage is 100%.

@@            Coverage Diff            @@
##           master    #236      +/-   ##
=========================================
- Coverage   83.68%   83.6%   -0.09%     
=========================================
  Files           5       5              
  Lines         754     750       -4     
=========================================
- Hits          631     627       -4     
  Misses        123     123

Impacted Files	Coverage Δ
tmuxp/cli.py	64.84% <100%> (+0.12%)	⬆️
tmuxp/workspacebuilder.py	95.54% <0%> (-0.14%)	⬇️

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[tony]

@rafi Thank for you this,

can you try adding a test?

You can use https://py.readthedocs.io/en/latest/path.html#py._path.local.LocalPath.mksymlinkto to make a symlink with pytest.

Example: https://github.com/pytest-dev/pytest/blob/6c8b0/testing/test_tmpdir.py#L88

[rafi]

@tony thanks for the pointers, added a test.

[tony]

This is now live in v1.3.0