Updates to the latest version of `rules_nodejs` that supports
the most recent NodeJS lts version v14.16.1.
Additionally the latest version of `rules_nodejs` provides
[a package for runfile resolution](https://github.com/bazelbuild/rules_nodejs/pull/2568) w/ types that we can leverage.
PR Close#41599
$(location) is not recommended in the bazel docs as depending on context it will either return the value of $(execpath) or $(rootpath). rules_nodejs now supports $(rootpath) and $(execpath) in templated_args of nodejs_binary.
PR Close#36308
Also add two targets to make it more convienent to tail & dump the sauce service logs: //tools/saucelabs:sauce_service_tail & //tools/saucelabs:sauce_service_log
PR Close#36109
* Added a /tools/saucelabs/sauce-service.sh script that manages the sauce-connect as a service which is used by the karma-saucelabs.js wrapper to start the service.
* Added /tools/saucelabs/README.md that covers the details of SauceLabs karma testing with Bazel.
PR Close#34769