refactor(techStackGeneric): improve readability

[ee7]

Description

A handful of miscellaneous refactoring-only changes while I was looking into #249:

• Clarify walkDir logic
• Prefer proc over template
• Remove unused variables
• Fix indentation

Testing

The existing tests should be sufficient.

The base branch was changed.

[ee7]

CI previously passed on this PR, but now fails despite no change to the PR. I believe the failure is unrelated:

main.go:62: error during command execution: unknown flag: --output-key-prefix

subprocess.CalledProcessError: Command '['cosign', 'generate-key-pair', '--output-key-prefix', 'chalk']' returned non-zero exit status 1.

[...]

Error: unknown flag: --tlog-upload

[...]

=========================== short test summary info >============================
FAILED test_command.py::test_setup_existing_keys[copy_files0-config1-False]
FAILED test_command.py::test_setup[config0-copy_files0] - subprocess.CalledPr...
FAILED test_command.py::test_setup[config1-copy_files0] - subprocess.CalledPr...
FAILED test_command.py::test_setup[config2-copy_files0] - subprocess.CalledPr...
FAILED test_command.py::test_setup_existing_keys[copy_files0-config0-True] - ...
======= 5 failed, 136 passed, 14 skipped, 1 warning in 273.03s (0:04:33) =======

[ee7]

CI passed the second time on f3c2137, I believe due to upstream fixing their version pinning of latest (so CI passes in this PR even without pinning the cosign version in the tests).

[ee7]

Happy to approve this again @miki725?

No intra-PR changes since your last approval, which got dismissed due to the branch change. I like stacked PRs, and prefer to merge them bottom-up, but I've never been happy with GitHub's handling of them.