test: run DatabaseMetadata tests for PG on emulator

Run the DatabaseMetadata integration tests for PostgreSQL-dialect databases
on the emulator.

Author: olavloite

src/test/java/com/google/cloud/spanner/jdbc/it/ITJdbcPgDatabaseMetaDataTest.java

@@ -61,10 +61,6 @@ public class ITJdbcPgDatabaseMetaDataTest extends ITAbstractJdbcTest {
 
   @BeforeClass
   public static void setup() throws Exception {
-    assumeFalse(
-        "PostgreSQL dialect is not yet supported on the emulator",
-        EmulatorSpannerHelper.isUsingEmulator());
-
     database = env.getOrCreateDatabase(Dialect.POSTGRESQL, getMusicTablesDdl(Dialect.POSTGRESQL));
 
     // Create the same tables in an additional 'test' schema.