build(deps): bump js-yaml, qs, shell-quote (incorporate PR #1001) (#1050)

PR #1001 (dependabot npm_and_yarn group) bumped js-yaml 4.1.1->4.2.0,
qs 6.15.0->6.15.2, and shell-quote 1.8.3->1.8.4. These were not yet
present in this branch. Rather than merging the dependabot merge commit
(baac44d) — which pulls in the entire divergent pre-probot-14.3.2 tree
and conflicts massively — the updates were applied surgically via
`npm update` against the current probot 14.3.2 lockfile, resolving to
equal-or-newer semver-compatible versions that fully cover PR #1001:
  js-yaml 4.1.1 -> 4.3.1
  qs      6.15.0 -> 6.15.3
  shell-quote 1.8.3 -> 1.10.0
plus related transitive bumps (js-yaml 3.14.2->3.15.1, side-channel).

Validated: unit/integration suite (344 passing; the 7 probot-ESM/Jest
suites fail pre-existing from the probot 14.3.2 migration, unrelated),
lockfile-lint clean, npm ls clean, and full live smoke-test (181 pass).

Co-authored-by: Copilot App <223556219+Copilot@users.noreply.github.com>

Author: decyjphr