chore(eslint): enable typescript 3.7 rules (#6765)

.eslintrc.js

lib/config/cli.ts

lib/config/migration.ts

lib/config/presets/index.ts

lib/datasource/dart/index.ts

lib/datasource/docker/index.ts

lib/datasource/github-tags/index.ts

lib/datasource/go/index.ts

lib/datasource/hex/index.ts

lib/datasource/maven/index.ts

lib/datasource/npm/get.ts

lib/datasource/packagist/index.ts

lib/datasource/pod/index.ts

lib/datasource/pypi/index.ts

lib/logger/utils.ts

lib/manager/bazel/update.ts

lib/manager/cocoapods/artifacts.ts

lib/manager/cocoapods/extract.ts

lib/manager/composer/artifacts.ts

lib/manager/composer/range.ts