[converter] Remove use of browserstack

[lina128]

Converter tests don't need browser to run. Remove browser brings down the test from ~8min to ~5min.

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This change is 

[nsthorat]

Reviewable status: 0 of 1 approvals obtained (waiting on @dsmilkov, @lina128, @nsthorat, and @pyu10055)

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tfjs-converter/package.json, line 61 at r1 (raw file):

    "link-local": "yalc link",
    "publish-local": "yarn build-npm && yalc push",
    "test": "yarn gen-json --test && karma start",

no more karma for local too right? let's make yarn test call node and call yarn test from test-ci

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tfjs-converter/package.json, line 62 at r1 (raw file):

    "publish-local": "yarn build-npm && yalc push",
    "test": "yarn gen-json --test && karma start",
    "test-ci": "yarn gen-json --test && yarn build && yarn lint && ts-node run_tests.ts",

can you update cloudbuild.yml there is a line called "test-browser" you can rename it

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tfjs-converter/package.json, line 64 at r1 (raw file):

    "test-ci": "yarn gen-json --test && yarn build && yarn lint && ts-node run_tests.ts",
    "test-snippets": "ts-node ./scripts/test_snippets.ts",
    "run-browserstack": "karma start --singleRun --browsers='bs_firefox_mac,bs_chrome_mac' --reporters='dots,karma-typescript,BrowserStack'",

remove this

[nsthorat]

Can you also make sure coverage hasn't decreased by running master against the CPU backend and make sure its the same number (looks like 470: https://pantheon.corp.google.com/cloud-build/builds/b3e40bd6-7734-4b76-98f8-576f3a2a3bb9;step=2?project=learnjs-174218)

[lina128]

Hi @nsthorat , thank you for your review! I cleaned up cloudbuild and package.json. Can you re-review the PR? And yes, the converage is the same.

[nsthorat]

Reviewed 2 of 3 files at r1.
Reviewable status: complete! 1 of 1 approvals obtained (waiting on @dsmilkov, @lina128, and @pyu10055)

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tfjs-converter/cloudbuild.yml, line 62 at r3 (raw file):

  entrypoint: 'bash'
  args: ['./run-python-tests.sh']
  waitFor: ['python-build']

how come do we have to wait for python-build now?

[lina128]

Reviewed 2 of 3 files at r1.
Reviewable status: complete! 1 of 1 approvals obtained (waiting on @dsmilkov, @lina128, and @pyu10055)

tfjs-converter/cloudbuild.yml, line 62 at r3 (raw file):

  entrypoint: 'bash'
  args: ['./run-python-tests.sh']
  waitFor: ['python-build']

how come do we have to wait for python-build now?

Ah, you are right, I thought the previous step is to build package, it's actually just testing package, so they can run in parallel. Changed back to before.