chore(java-spanner): add library to generation_config.yaml

Author: chingor13

generation_config.yaml

@@ -2464,6 +2464,32 @@ libraries:
   - proto_path: google/shopping/merchant/reviews/v1beta
   requires_billing: true
   library_name: shopping-merchant-reviews
+- api_shortname: spanner
+  name_pretty: Cloud Spanner
+  product_documentation: https://cloud.google.com/spanner/docs/
+  client_documentation: https://cloud.google.com/java/docs/reference/google-cloud-spanner/latest/history
+  api_description: is a fully managed, mission-critical,  relational database service
+    that offers transactional consistency at global scale, schemas, SQL (ANSI 2011
+    with extensions), and automatic, synchronous replication for high availability.
+    Be sure to activate the Cloud Spanner API on the Developer's Console to use Cloud
+    Spanner from your project.
+  issue_tracker: https://issuetracker.google.com/issues?q=componentid:190851%2B%20status:open
+  release_level: stable
+  language: java
+  min_java_version: 8
+  distribution_name: com.google.cloud:google-cloud-spanner
+  api_id: spanner.googleapis.com
+  transport: grpc
+  requires_billing: true
+  codeowner_team: '@googleapis/spanner-team'
+  library_type: GAPIC_COMBO
+  excluded_poms: google-cloud-spanner-bom
+  recommended_package: com.google.cloud.spanner
+  GAPICs:
+  - proto_path: google/spanner/admin/database/v1
+  - proto_path: google/spanner/admin/instance/v1
+  - proto_path: google/spanner/executor/v1
+  - proto_path: google/spanner/v1
 - api_shortname: spanneradapter
   name_pretty: Cloud Spanner Adapter API
   product_documentation: https://cloud.google.com/java/docs/reference/google-cloud-spanneradapter/latest/overview