fix(looker): various looker fixes

[gabe-lyons]

1. uses logger.info instead of warn when the type cannot be mapped
2. permits the passing of transport_options to looker client
3. provides view_logic as the view file contents in the case no view logic can be otherwise provided.

Checklist

• The PR conforms to DataHub's Contributing Guideline (particularly Commit Message Format)
• Links to related issues (if applicable)
• Tests for the changes have been added/updated (if applicable)
• Docs related to the changes have been added/updated (if applicable)

[github-actions]

Unit Test Results (build & test)

  92 files  ±0    92 suites  ±0   21m 8s ⏱️ - 1m 38s
672 tests ±0  613 ✔️ ±0  59 💤 ±0  0 ❌ ±0 

Results for commit 4b305eb. ± Comparison against base commit bb413be.

♻️ This comment has been updated with latest results.

[github-actions]

Unit Test Results (metadata ingestion)

       5 files         5 suites   50m 19s ⏱️
   362 tests    362 ✔️   0 💤 0 ❌
1 657 runs  1 626 ✔️ 31 💤 0 ❌

Results for commit 4b305eb.

♻️ This comment has been updated with latest results.

[rslanka]

Hi @gabe-lyons, I don't think we actually need pass the per-request transport_options to each cli call as done in this PR, since every request is passed the same set of options. I think this can be done once during init31 to set these params for all subsequent calls via the client. Please let me know if I am missing something.

[rslanka]

LGTM!

Looker is hardcoding the headers. Until that gets fixed, what you have done seems to be only way forward for us.