Allow build to early exit on no significant changes

[jleach]

Now that the iOS and Android native build are required checks it can take a long time to get a PR checked if it updates a non core file like README. This PR adds a check to see where the files were changed if if they are not significant allow an early exit on these steps.

[jleach]

I think like 101 should have || true after the grep command but that causes the script to fail when run as an action.

Working

change_count=$(echo "$diff_output" | grep -E '^(app/.*)|(.yarn/.*)|(.github/workflows/.*)' | wc -l | awk '{$1=$1};1' || true)

Fails

change_count=$(echo "$diff_output" | grep -E '^(app/.*)|(.yarn/.*)|(.github/workflows/.*)' || true | wc -l | awk '{$1=$1};1')

Comparing origin/main with HEAD
++ git diff --name-only origin/main..HEAD
+ diff_output=.github/workflows/main.yaml
++ echo .github/workflows/main.yaml
++ grep -E '^(app/.*)|(.yarn/.*)|(.github/workflows/.*)'
+ change_count=.github/workflows/main.yaml
.github/workflows/main.yaml files changed in app, .yarn, or .github/workflows
+ echo '.github/workflows/main.yaml files changed in app, .yarn, or .github/workflows'
+ '[' .github/workflows/main.yaml -gt 0 ']'
/home/runner/work/_temp/c6[40](https://github.com/bcgov/bc-wallet-mobile/actions/runs/11559048112/job/32172842752?pr=2240#step:3:41)cb30-5955-4315-812b-7e7c26d28ccf.sh: line 22: [: .github/workflows/main.yaml: integer expression expected
+ echo result=false