[test] Temporarily set client-pool-size to 1 in Spark PaimonHiveTestBase (#5308)

Author: Zouxxyy

.github/workflows/utitcase-spark-4.x.yml

@@ -58,6 +58,6 @@ jobs:
           test_modules+="org.apache.paimon:paimon-spark-${suffix},"
           done
           test_modules="${test_modules%,}"
-          mvn -T 1C -B test -pl "${test_modules}" -Duser.timezone=$jvm_timezone -Pspark4
+          mvn -T 2C -B test -pl "${test_modules}" -Duser.timezone=$jvm_timezone -Pspark4
         env:
           MAVEN_OPTS: -Xmx4096m

paimon-spark/paimon-spark-ut/src/test/scala/org/apache/paimon/spark/PaimonHiveTestBase.scala

@@ -50,6 +50,8 @@ class PaimonHiveTestBase extends PaimonSparkTestBase {
       .set("spark.sql.warehouse.dir", tempHiveDBDir.getCanonicalPath)
       .set("spark.sql.catalogImplementation", "hive")
       .set(s"spark.sql.catalog.$sparkCatalogName", "org.apache.paimon.spark.SparkGenericCatalog")
+      // remove this, when fix https://github.com/apache/paimon/issues/5307
+      .set(s"spark.sql.catalog.$sparkCatalogName.client-pool-size", "1")
       .set(s"spark.sql.catalog.$paimonHiveCatalogName", classOf[SparkCatalog].getName)
       .set(s"spark.sql.catalog.$paimonHiveCatalogName.metastore", "hive")
       .set(s"spark.sql.catalog.$paimonHiveCatalogName.warehouse", tempHiveDBDir.getCanonicalPath)