[ESQL] Fix sorting on CSV test (#113689)

Resolves #113632

Fixes a test that relied on order without sorting.

muted-tests.yml

@@ -302,9 +302,6 @@ tests:
 - class: org.elasticsearch.integration.KibanaUserRoleIntegTests
   method: testSearchAndMSearch
   issue: https://github.com/elastic/elasticsearch/issues/113593
-- class: org.elasticsearch.xpack.esql.qa.mixed.MixedClusterEsqlSpecIT
-  method: test {date_nanos.Date_nanos to date nanos, index version SYNC}
-  issue: https://github.com/elastic/elasticsearch/issues/113632
 - class: org.elasticsearch.xpack.transform.integration.TransformIT
   method: testStopWaitForCheckpoint
   issue: https://github.com/elastic/elasticsearch/issues/106113

x-pack/plugin/esql/qa/testFixtures/src/main/resources/date_nanos.csv-spec

@@ -204,7 +204,7 @@ null
 date nanos to long, index version
 required_capability: to_date_nanos
 
-FROM date_nanos | WHERE millis > "2020-02-02" | EVAL l = TO_LONG(nanos) | KEEP l;
+FROM date_nanos | WHERE millis > "2020-02-02" | EVAL l = TO_LONG(nanos) | SORT nanos DESC | KEEP l;
 
 l:long
 1698069301543123456
@@ -219,7 +219,7 @@ l:long
 long to date nanos, index version
 required_capability: to_date_nanos
 
-FROM date_nanos | WHERE millis > "2020-02-02" | EVAL d = TO_DATE_NANOS(num) | KEEP d;
+FROM date_nanos | WHERE millis > "2020-02-02" | EVAL d = TO_DATE_NANOS(num) | SORT nanos DESC | KEEP d;
 
 d:date_nanos
 2023-10-23T13:55:01.543123456Z
@@ -234,7 +234,7 @@ d:date_nanos
 date_nanos to date nanos, index version
 required_capability: to_date_nanos
 
-FROM date_nanos | WHERE millis > "2020-02-02" | EVAL d = TO_DATE_NANOS(nanos) | KEEP d;
+FROM date_nanos | WHERE millis > "2020-02-02" | EVAL d = TO_DATE_NANOS(nanos) | SORT nanos DESC | KEEP d;
 
 d:date_nanos
 2023-10-23T13:55:01.543123456Z