Migrate CircleCI unit test workflow to Github (contrib)

[shovnik]

Which problem is this PR solving?

• This addresses issue by migrating the only existing opentelemetry-js-contrib workflow from CircleCI to GitHub Actions (config.yml)

Short description of the changes

• Migrate node-unit-tests and browser-unit-tests contained in config.yml file to GitHub Actions
• Change lint workflow trigger to be on pull_request and push as well to avoid overlapping triggers
• Minor unrelated lint fix so that the lint test stops failing for every PR on the contrib repo

Migration Plan

I suggest having CircleCI and GitHub Action jobs run in parallel for a few weeks. After the GitHub Action jobs are running fine for a week or so and then remove the CircleCI workflows from config.yml

cc - @alolita

[codecov]

Codecov Report

Merging #272 (a05081e) into master (d896904) will decrease coverage by 0.26%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #272      +/-   ##
==========================================
- Coverage   95.07%   94.81%   -0.27%     
==========================================
  Files         110        8     -102     
  Lines        5888      212    -5676     
  Branches      607       25     -582     
==========================================
- Hits         5598      201    -5397     
+ Misses        290       11     -279     

Impacted Files	Coverage Δ
node/opentelemetry-plugin-dns/src/utils.ts
...entelemetry-instrumentation-graphql/test/schema.ts
...ns/node/opentelemetry-plugin-pg/test/utils.test.ts
...s/web/opentelemetry-plugin-react-load/.eslintrc.js
node/opentelemetry-plugin-mysql/src/mysql.ts
.../opentelemetry-plugin-mongodb/test/mongodb.test.ts
.../opentelemetry-hapi-instrumentation/src/version.ts
node/opentelemetry-plugin-mongodb/src/types.ts
...entelemetry-hapi-instrumentation/test/hapi.test.ts
...opentelemetry-instrumentation-graphql/.eslintrc.js
... and 91 more

[shovnik]

I deleted the CircleCI workflow file, but to complete the migration a maintainer needs to remove the CircleCi webhook in the repository settings before merging this PR.