Add missing EsqlFunctionRegistry import in AnalyzerTests

Author: felixbarny

x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/analysis/AnalyzerTests.java

@@ -55,6 +55,7 @@
 import org.elasticsearch.xpack.esql.datasources.spi.StoragePath;
 import org.elasticsearch.xpack.esql.enrich.ResolvedEnrichPolicy;
 import org.elasticsearch.xpack.esql.expression.Order;
+import org.elasticsearch.xpack.esql.expression.function.EsqlFunctionRegistry;
 import org.elasticsearch.xpack.esql.expression.function.UnsupportedAttribute;
 import org.elasticsearch.xpack.esql.expression.function.aggregate.Count;
 import org.elasticsearch.xpack.esql.expression.function.aggregate.FilteredExpression;