style: Remove unused imports in BuildInSqlFunctionTable to fix checkstyle violations

- Remove unused import: ConnectedComponents
- Remove unused import: LabelPropagation
- Remove unused import: Louvain

These imports were added during merge but not actually used in the code.
Checkstyle was failing with UnusedImports warnings.

Author: kitalkuyo-gita

geaflow/geaflow-dsl/geaflow-dsl-plan/src/main/java/org/apache/geaflow/dsl/schema/function/BuildInSqlFunctionTable.java

@@ -38,7 +38,6 @@
 import org.apache.geaflow.dsl.udf.graph.ClosenessCentrality;
 import org.apache.geaflow.dsl.udf.graph.ClusterCoefficient;
 import org.apache.geaflow.dsl.udf.graph.CommonNeighbors;
-import org.apache.geaflow.dsl.udf.graph.ConnectedComponents;
 import org.apache.geaflow.dsl.udf.graph.GraphSAGE;
 import org.apache.geaflow.dsl.udf.graph.IncKHopAlgorithm;
 import org.apache.geaflow.dsl.udf.graph.IncMinimumSpanningTree;
@@ -47,8 +46,6 @@
 import org.apache.geaflow.dsl.udf.graph.JaccardSimilarity;
 import org.apache.geaflow.dsl.udf.graph.KCore;
 import org.apache.geaflow.dsl.udf.graph.KHop;
-import org.apache.geaflow.dsl.udf.graph.LabelPropagation;
-import org.apache.geaflow.dsl.udf.graph.Louvain;
 import org.apache.geaflow.dsl.udf.graph.PageRank;
 import org.apache.geaflow.dsl.udf.graph.SingleSourceShortestPath;
 import org.apache.geaflow.dsl.udf.graph.TriangleCount;