[O11y][GCP Load balancing] Lens Migration

[rajvi-patel-22]

Manually migrate GCP Load balancing visualizations to the lens in the current Kibana version 8.7.1 itself.

Preparation of data for testing

• Use sample_event.json / setup live instance using docker / mock data using a mock server to populate dashboards

Migration stats

	Before Migration			After Migration
	Lens	Vizualization	Old Control panels	Lens	Vizualization	New Input controls
[Metrics GCP] Load Balancing TCP SSL Proxy Overview	0	5	1	5	0	1
[Metrics GCP] Load Balancing L3 Overview	0	4	1	4	0	1
[Metrics GCP] Load Balancing HTTPS Overview	0	6	1	6	0	1

Dashboard : Load Balancing TCP SSL Proxy Overview

• Migrate 5 visualization to lens and 1 old controls to new input controls.
  • [O11y][GCP]Migrate GCP Load Balancing TCP SSL Proxy Overview dashboard to lens #7459

Dashboard : Load Balancing L3 Proxy Overview

• Migrate 4 visualization to lens and 1 old controls to new input controls.
  • [O11y][GCP] Migrate GCP Load Balancing L3 Overview dashboard to lens #7461

Dashboard : Load Balancing HTTPS Proxy Overview

• Migrate 6 visualization to lens and 1 old controls to new input controls.
  • [O11y][GCP] Migrate GCP Load Balancing HTTPS Overview dashboard to lens #7458

Verification and Validation

• Verification of functionality remains the same after migration in Kibana
• Verification of data count of after-migrated visualization with before-migrated visualization in Kibana
• Verification of Dashboards is not distorted in the supported Kibana version (TBD)

[rajvi-patel-22]

The dashboards contain incorrect fields. Hence, lens migration task is blocked due to this issue: #7242