simplified expr string type timestamp cast, fixed checkstyle failure

Signed-off-by: Matthew Wells <[email protected]>

Author: matthewryanwells

core/src/main/java/org/opensearch/sql/data/model/ExprStringValue.java

@@ -40,16 +40,9 @@ public Instant timestampValue() {
     try {
       return new ExprTimestampValue(value).timestampValue();
     } catch (SemanticCheckException e) {
-      try {
-        return new ExprTimestampValue(
-                LocalDateTime.of(new ExprDateValue(value).dateValue(), LocalTime.of(0, 0, 0)))
-            .timestampValue();
-      } catch (SemanticCheckException exception) {
-        throw new SemanticCheckException(
-            String.format(
-                "timestamp:%s in unsupported format, please use 'yyyy-MM-dd HH:mm:ss[.SSSSSSSSS]'",
-                value));
-      }
+      return new ExprTimestampValue(
+              LocalDateTime.of(new ExprDateValue(value).dateValue(), LocalTime.of(0, 0, 0)))
+          .timestampValue();
     }
   }
 

opensearch/src/test/java/org/opensearch/sql/opensearch/storage/script/filter/FilterQueryBuilderTest.java

@@ -1628,8 +1628,9 @@ void cast_to_date_in_filter() {
         ref("date_value", DATE), DSL.castDate(literal("2021-11-08")))));
     assertJsonEquals(json, buildQuery(DSL.equal(
         ref("date_value", DATE), DSL.castDate(literal(new ExprDateValue("2021-11-08"))))));
-    assertJsonEquals(json, buildQuery(DSL.equal(ref(
-        "date_value", DATE), DSL.castDate(literal(new ExprTimestampValue("2021-11-08 17:00:00"))))));
+    assertJsonEquals(json, buildQuery(DSL.equal(
+        ref("date_value", DATE), DSL.castDate(
+            literal(new ExprTimestampValue("2021-11-08 17:00:00"))))));
   }
 
   @Test