fix: create constants for `skipReason` (#5660)

lib/manager/ansible-galaxy/extract.ts

lib/manager/bazel/extract.ts

lib/manager/buildkite/extract.ts

lib/manager/bundler/extract.ts

lib/manager/cargo/extract.ts

lib/manager/cocoapods/extract.ts

lib/manager/common.ts

lib/manager/composer/extract.ts

lib/manager/dockerfile/extract.ts

lib/manager/gitlabci-include/extract.ts

lib/manager/gomod/extract.ts

lib/manager/helm-requirements/extract.ts

lib/manager/helmfile/extract.ts

lib/manager/homebrew/extract.ts

lib/manager/maven/extract.ts

lib/manager/mix/extract.ts

lib/manager/npm/extract/index.ts

lib/manager/nuget/__snapshots__/extract.spec.ts.snap

lib/manager/nuget/extract.ts

lib/manager/pip_requirements/extract.ts