[Dashboard] Add error handling for the requests in Dashboard

[DanielZhangQD]

Add error handling for the requests in Dashboard - throw error for unexpected error cases and the get function in the dashboard cache will catch the errors without updating the cached data.

Tested (run the relevant ones):

• Code formatting: install pre-commit (auto-check on commit) or bash format.sh

• Any manual or new tests for this PR (please specify below)

  • Clusters page, cluster table will not be cleared with 5xx response
  • Managed jobs page, managed job table will not be cleared with 5xx response
  • Users page, user table will not be cleared with 5xx response
  • Volumes page, volume table will not be cleared with 5xx response
  • Configuration page, no unexpected error with 5xx response
  • Workspace page, no unexpected error with 5xx response
  • Infra page, no unexpected error with 5xx response

• All smoke tests: /smoke-test (CI) or pytest tests/test_smoke.py (local)

• Relevant individual tests: /smoke-test -k test_name (CI) or pytest tests/test_smoke.py::test_name (local)

• Backward compatibility: /quicktest-core (CI) or pytest tests/smoke_tests/test_backward_compat.py (local)

[aylei]

LGTM, thanks @DanielZhangQD !