Move FIPS test utility into internal/testutil module

Author: ycombinator

internal/testutil/README.md

@@ -0,0 +1,4 @@
+## Test Utilities
+
+The `go.opentelemetry.io/collector/internal/testutil` module provides utility functions, etc. for use by tests in other 
+OpenTelemetry Collector modules.

testutils/fips.go renamed to internal/testutil/fips.go

@@ -1,7 +1,7 @@
 // Copyright The OpenTelemetry Authors
 // SPDX-License-Identifier: Apache-2.0
 
-package testutils // import "go.opentelemetry.io/collector/testutils"
+package testutil // import "go.opentelemetry.io/collector/internal/testutil"
 
 import (
 	"os"

internal/testutil/go.mod

@@ -0,0 +1,15 @@
+module go.opentelemetry.io/collector/internal/testutil
+
+go 1.24.0
+
+require (
+	github.com/stretchr/testify v1.11.1
+	go.uber.org/goleak v1.3.0
+)
+
+require (
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/kr/text v0.2.0 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
+)