REF: replace find-with-or with function

[klauer]

• plc-tmo-vac is skipping over files for some bizarre reason: https://github.com/pcdshub/lcls-plc-tmo-vac/actions/runs/4429313692/jobs/7769595993
• I can reproduce this locally with just a simple bash script on the tmo project:

#!/bin/bash

while IFS= read -r -d '' source_filename; do
    echo "Checking ${source_filename}"
done < <(find "." -type f -iname '*.TcDUT' -or -iname '*.TcGVL' -or -iname '*.TcPOU' -print0)

$ find . -name "*.Tc*" |wc -l
33
(^ this includes 3 TcTTO files we don't care about so our target is 30 files)
$ bash reproducing_gha.sh  |wc -l
19
$ bash pr.sh | wc -l
30

(If someone can clue me in what I'm doing wrong there - I'd certainly appreciate it...) In the meantime, the workaround in this PR seems to be fine as in the above file count listing.

[tangkong]

Apparently find with a command at the end only works on the last criterion unless you group the expression in \( \). This works for me:

#!/bin/bash

while IFS= read -r -d '' source_filename; do
    echo "Checking ${source_filename}"
done < <(find "." -type f \( -iname '*.TcDUT' -or -iname '*.TcGVL' -or -iname '*.TcPOU' \) -print0)

I won't take credit for this, stack exchange can

[klauer]

Well, I'll be... !

Regardless of where you got it, thanks for digging and figuring out the actual fix. Let me update this PR.