build(deps): Add shtab

See also:
- https://github.com/iterative/shtab
- https://docs.iterative.ai/shtab/

Author: tony

poetry.lock

@@ -61,6 +61,7 @@ vcspull = 'vcspull:cli.cli'
 python = "^3.9"
 libvcs = "~0.17.0"
 colorama = ">=0.3.9"
+shtab = "^1.5.5"
 
 [tool.poetry.dev-dependencies]
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