chore: Add gcp resouce name span attribute

Author: surbhigarg92

observability-test/observability.ts

@@ -126,7 +126,10 @@ describe('startTrace', () => {
   });
 
   it('with semantic attributes', () => {
-    const opts = {tableName: 'table', dbName: 'db'};
+    const opts = {
+      tableName: 'table',
+      dbName: 'projects/PROJECT_ID/instances/INSTANCE_ID/databases/DATABASE_ID',
+    };
     startTrace('aSpan', opts, span => {
       assert.equal(
         span.attributes[ATTR_OTEL_SCOPE_NAME],
@@ -158,6 +161,12 @@ describe('startTrace', () => {
         'Missing gcp.client.repo attribute',
       );
 
+      assert.equal(
+        span.attributes['gcp.resource.name'],
+        '//spanner.googleapis.com/projects/PROJECT_ID/instances/INSTANCE_ID/databases/DATABASE_ID',
+        'Missing gcp.resource.name attribute',
+      );
+
       assert.equal(
         span.attributes[SEMATTRS_DB_SQL_TABLE],
         'table',

src/instrument.ts

@@ -150,6 +150,10 @@ export function startTrace<T>(
         span.setAttribute('db.sql.table', config.tableName);
       }
       if (config.dbName) {
+        span.setAttribute(
+          'gcp.resource.name',
+          `//spanner.googleapis.com/${config.dbName}`,
+        );
         span.setAttribute('db.name', config.dbName);
       }
       if (config.requestTag) {