* ci: add package-lock.json registry check and pin npm registry
Prevents contributors using mirror registries (e.g. npmmirror.com) from
rewriting all resolved URLs in package-lock.json, which also causes
cascading formatting changes due to different dependency versions.
* fix(ci): use || true instead of || echo 0 in registry check
When all resolved URLs are standard, grep -cv outputs 0 and exits with
code 1. The || echo 0 then fires and also outputs 0, making BAD_COUNT
"0\n0" which causes a bash integer expression error. Using || true
swallows the exit code without extra output.
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Co-authored-by: Kondamon <kondamon@github.com>