test(completion): Add tests for bash completion functionality

[ashelly]

Relative: revup_completion_bash
Topic: completion_tests

Test helper functions and completion script generation for commands

[ashelly]

Reviews in this chain:
└#2 Feature: revup completion for bash
　└#11 test(completion): Add tests for bash completion functionality

[ashelly]

#	head	base	diff	date	summary
0	b8a951f2	8bc48489	diff	Feb 3 18:05 PM	1 file changed, 132 insertions(+)
1	087f5243	8bc48489	diff	Feb 4 17:36 PM	1 file changed, 123 insertions(+), 78 deletions(-)
2	087f5243	8bc48489	diff	Feb 4 17:37 PM	0 files changed