[develop] Fix WE2E yaml configuration file for MET_verification_only_vx

[gsketefian]

Expected behavior

The WE2E test MET_verification_only_vx should succeed.

Current behavior

Currently, MET_verification_only_vx fails because in its configuration file, the variables CCPA_OBS_DIR, MRMS_OBS_DIR, and NDAS_OBS_DIR are under the wrong section (they are under workflow_switches; they need to be under platform). The python script run_WE2E_tests.py detects this and aborts the test.

This failure was not detected earlier (i.e. when the test MET_verification_only_vx was created in PR #566) possibly because at the time local tests were conducted with a version of the App that was not updated with PR #541 and/or because the test was run with the shell script run_WE2E_tests.sh instead of its python counterpart run_WE2E_tests.py.

Machines affected

All.

Steps To Reproduce

Run the WE2E test MET_verification_only_vx using the python script run_WE2E_tests.py.

Detailed Description of Fix (optional)

In config.MET_verification_only_vx.yaml, create a new section named platform and move the variables CCPA_OBS_DIR, MRMS_OBS_DIR, and NDAS_OBS_DIR there.