Update module github.com/openshift/imagebuilder to v1.2.15

Signed-off-by: renovate[bot] <29139614+renovate[bot]@users.noreply.github.com>

vendor/github.com/moby/buildkit/util/stack/stack.go

@@ -46,22 +46,23 @@ func Helper() {
 func Traces(err error) []*Stack {
 	var st []*Stack
 
-	wrapped, ok := err.(interface {
-		Unwrap() error
-	})
-	if ok {
-		st = Traces(wrapped.Unwrap())
+	switch e := err.(type) {
+	case interface{ Unwrap() error }:
+		st = Traces(e.Unwrap())
+	case interface{ Unwrap() []error }:
+		for _, ue := range e.Unwrap() {
+			st = Traces(ue)
+			// Only take first stack
+			if len(st) > 0 {
+				break
+			}
+		}
 	}
 
-	if ste, ok := err.(interface {
-		StackTrace() errors.StackTrace
-	}); ok {
+	switch ste := err.(type) {
+	case interface{ StackTrace() errors.StackTrace }:
 		st = append(st, convertStack(ste.StackTrace()))
-	}
-
-	if ste, ok := err.(interface {
-		StackTrace() *Stack
-	}); ok {
+	case interface{ StackTrace() *Stack }:
 		st = append(st, ste.StackTrace())
 	}
 

vendor/github.com/moby/buildkit/util/stack/stack.pb.go

@@ -1,6 +1,6 @@
 // Code generated by protoc-gen-go. DO NOT EDIT.
 // versions:
-// 	protoc-gen-go v1.30.0
+// 	protoc-gen-go v1.33.0
 // 	protoc        v3.11.4
 // source: stack.proto
 

vendor/github.com/moby/buildkit/util/stack/stack.proto

@@ -3,15 +3,15 @@ syntax = "proto3";
 package stack;
 
 message Stack {
-    repeated Frame frames = 1;
-    repeated string cmdline = 2;
-    int32 pid = 3;
-    string version = 4;
-    string revision = 5;
+	repeated Frame frames = 1;
+	repeated string cmdline = 2;
+	int32 pid = 3;
+	string version = 4;
+	string revision = 5;
 }
 
 message Frame {
-    string Name = 1;
-    string File = 2;
-    int32 Line = 3;
+	string Name = 1;
+	string File = 2;
+	int32 Line = 3;
 }