Issue description

Google Spanner not return after insert

Expected Behavior

Hi,

I'm using Spanner database and it has returning option supported.

Documentation Spanner Returning data after insert:
https://cloud.google.com/spanner/docs/reference/postgresql/dml-syntax#insert-returning

Actual Behavior

But typeorm is give error:
'OUTPUT or RETURNING clause only supported by Microsoft SQL Server or PostgreSQL or MariaDB databases.'

Steps to reproduce

const result = await queryRunner.manager
.createQueryBuilder()
.insert()
.into(CostCenter)
.values(entity)
.updateEntity(false)
.returning(['id'])
.execute(); // Executes pure INSERT/**/

OR/AND

const result = await queryRunner.manager.insert(CostCenter, entity);

My Environment

Additional Context

No response

Relevant Database Driver(s)

• aurora-mysql
• aurora-postgres
• better-sqlite3
• cockroachdb
• cordova
• expo
• mongodb
• mysql
• nativescript
• oracle
• postgres
• react-native
• sap
• spanner
• sqlite
• sqlite-abstract
• sqljs
• sqlserver

Are you willing to resolve this issue by submitting a Pull Request?

Yes, I have the time, and I know how to start.