Update preinstall script to update agent config from V2 to V3 (#999) #4790

Job	Run time
Lint	4m 9s
Performance Tests	4m 48s
Unit tests with race condition detection	2m 30s
Build Unsigned Snapshot	1m 46s
Unit Tests	2m 7s
Load Tests	4m 20s
Integration Tests (ubuntu, 22.04)	9m 13s
Integration Tests - Official Plus Images (alpine, 3.20, r32, alpine, /nginx-plus/agent)	5m 54s
Integration Tests (redhatenterprise, 9)	8m 27s
Integration Tests - Official OSS Images (bookworm, stable, debian)	6m 12s
Integration Tests - Official Plus Images (alpine, 3.19, r31, alpine, /nginx-plus/agent)	5m 55s
Integration Tests (alpine, 3.19)	6m 39s
Integration Tests - Official OSS Images (bookworm, mainline, debian)	6m 4s
Integration Tests - Official Plus Images (debian, bookworm, r32, debian, /nginx-plus/agent)	6m 12s
Integration Tests - Official Plus Images (debian, bookworm, r31, debian, /nginx-plus/agent)	6m 1s
Integration Tests - Official OSS Images (alpine, stable, alpine)	6m 2s
Integration Tests - Official OSS Images (alpine, mainline, alpine)	5m 54s
Publish NGINX Agent v3 packages / Set workflow variables	5s
Publish NGINX Agent v3 packages / Update Release Draft	5s
Publish NGINX Agent v3 packages / Tag Release	5s
Publish NGINX Agent v3 packages / Upload packages	18m 10s
Publish NGINX Agent v3 packages / Merge release branch back into V3 branch	0s
	1h 50m 38s

Provide feedback