Worker: allow configuring executor CloudWatch group

We need the ability to use different CloudWatch group for the
osbuild-executor on Fedora workers in staging and production
environment.

Extend the worker confguration to allow configuring the CloudWatch group
name used by the osbuild-executor. Extend the secure instance code to
instruct cloud-init via user data to create /tmp/cloud_init_vars file
with the CloudWatch group name in the osbuild-executor instance, to make
it possible for the executor to configure its logging differently based
on the value.

Cover new changes by unit tests.

Signed-off-by: Tomáš Hozza <thozza@redhat.com>

internal/cloud/awscloud/secure-instance_test.go

@@ -0,0 +1,43 @@
+package awscloud
+
+import (
+	"fmt"
+	"testing"
+)
+
+func TestSecureInstanceUserData(t *testing.T) {
+	type testCase struct {
+		CloudWatchGroup  string
+		ExpectedUserData string
+	}
+
+	testCases := []testCase{
+		{
+			ExpectedUserData: `#cloud-config
+write_files:
+  - path: /tmp/worker-run-executor-service
+    content: ''
+`,
+		},
+		{
+			CloudWatchGroup: "test-group",
+			ExpectedUserData: `#cloud-config
+write_files:
+  - path: /tmp/worker-run-executor-service
+    content: ''
+  - path: /tmp/cloud_init_vars
+    content: |
+      OSBUILD_EXECUTOR_CLOUDWATCH_GROUP='test-group'
+`,
+		},
+	}
+
+	for idx, tc := range testCases {
+		t.Run(fmt.Sprintf("Test case %d", idx), func(t *testing.T) {
+			userData := SecureInstanceUserData(tc.CloudWatchGroup)
+			if userData != tc.ExpectedUserData {
+				t.Errorf("Expected: %s, got: %s", tc.ExpectedUserData, userData)
+			}
+		})
+	}
+}