[launcher] Trim CCEL padding #3315

Job	Run time
Generate/Build/Test (macos-14-large, x64, Go 1.24.x)	1m 58s
Generate/Build/Test (ubuntu-latest, x64, Go 1.24.x)	6m 39s
Lint ./launcher (ubuntu-latest, Go 1.24.x)	4m 25s
Generate/Build/Test (ubuntu-latest, x32, Go 1.24.x)	3m 28s
Generate/Build/Test (macos-latest, arm64, Go 1.24.x)	1m 30s
Lint CGO (ubuntu-latest, Go 1.24.x)	3m 23s
Lint ./ (ubuntu-latest, Go 1.24.x)	3m 22s
Lint ./keymanager (ubuntu-latest, Go 1.24.x)	3m 34s
Lint ./cmd (ubuntu-latest, Go 1.24.x)	4m 3s
	32m 22s

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