cmd/hi: improve test cleanup to reduce CI disk usage (#2881)

integration/dockertestutil/build.go

@@ -1,17 +1,25 @@
 package dockertestutil
 
 import (
+	"context"
 	"os/exec"
+	"time"
 )
 
 // RunDockerBuildForDiagnostics runs docker build manually to get detailed error output.
 // This is used when a docker build fails to provide more detailed diagnostic information
 // than what dockertest typically provides.
-func RunDockerBuildForDiagnostics(contextDir, dockerfile string) string {
-	cmd := exec.Command("docker", "build", "-f", dockerfile, contextDir)
+//
+// Returns the build output regardless of success/failure, and an error if the build failed.
+func RunDockerBuildForDiagnostics(contextDir, dockerfile string) (string, error) {
+	// Use a context with timeout to prevent hanging builds
+	const buildTimeout = 10 * time.Minute
+
+	ctx, cancel := context.WithTimeout(context.Background(), buildTimeout)
+	defer cancel()
+
+	cmd := exec.CommandContext(ctx, "docker", "build", "--progress=plain", "--no-cache", "-f", dockerfile, contextDir)
 	output, err := cmd.CombinedOutput()
-	if err != nil {
-		return string(output)
-	}
-	return ""
+
+	return string(output), err
 }