build: add BUILD_ prefix

build/ci.go

@@ -667,7 +667,7 @@ func doDebianSource(cmdline []string) {
 	maybeSkipArchive(env)
 
 	// Import the signing key.
-	if key := getenvBase64("PPA_SIGNING_KEY"); len(key) > 0 {
+	if key := getenvBase64("BUILD_PPA_SIGNING_KEY"); len(key) > 0 {
 		gpg := exec.Command("gpg", "--import")
 		gpg.Stdin = bytes.NewReader(key)
 		build.MustRun(gpg)

internal/build/env.go

@@ -92,7 +92,7 @@ func Env() Environment {
 			IsCronJob:     os.Getenv("APPVEYOR_SCHEDULED_BUILD") == "True",
 		}
 
-	case os.Getenv("CI") == "true" && os.Getenv("ETH_BUILDBOT") == "true":
+	case os.Getenv("BUILD_ETH_BUILDBOT") == "true":
 		// For buildbot, the branch variable is the branch OR tag, and
 		// we can distinguish them by the git refspec.
 		var branch, tag string