tests: Move MustAbsPath function to testutils

Signed-off-by: Marek Siarkowicz <siarkowicz@google.com>

tests/framework/testutils/path.go

@@ -0,0 +1,25 @@
+// Copyright 2022 The etcd Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package testutils
+
+import "path/filepath"
+
+func MustAbsPath(path string) string {
+	abs, err := filepath.Abs(path)
+	if err != nil {
+		panic(err)
+	}
+	return abs
+}