EsqlTestUtilsTests: add checks for PromQL availability (#138882)

fixes #138879

Author: felixbarny

x-pack/plugin/esql/qa/testFixtures/src/test/java/org/elasticsearch/xpack/esql/EsqlTestUtilsTests.java

@@ -8,6 +8,7 @@
 package org.elasticsearch.xpack.esql;
 
 import org.elasticsearch.test.ESTestCase;
+import org.elasticsearch.xpack.esql.action.PromqlFeatures;
 
 import java.util.Set;
 
@@ -16,6 +17,7 @@
 public class EsqlTestUtilsTests extends ESTestCase {
 
     public void testPromQL() {
+        assumeTrue("requires snapshot build with promql feature enabled", PromqlFeatures.isEnabled());
         assertThat(
             EsqlTestUtils.addRemoteIndices("PROMQL foo, bar step 1m (avg(baz))", Set.of(), false),
             equalTo("PROMQL *:foo,foo,*:bar,bar step 1m (avg(baz))")
@@ -27,6 +29,7 @@ public void testPromQL() {
     }
 
     public void testPromQLDefaultIndex() {
+        assumeTrue("requires snapshot build with promql feature enabled", PromqlFeatures.isEnabled());
         assertThat(
             EsqlTestUtils.addRemoteIndices("PROMQL step 1m (avg(baz))", Set.of(), false),
             equalTo("PROMQL *:*,* step 1m (avg(baz))")