[Spotless] Applying Google Code Format for ppl files #12 (opensearch-project#1972)

* Spotless apply on PPL (#339)

Signed-off-by: Mitchell Gale <[email protected]>

* Update ppl/src/test/java/org/opensearch/sql/ppl/parser/AstExpressionBuilderTest.java

Co-authored-by: Guian Gumpac <[email protected]>
Signed-off-by: Mitchell Gale <[email protected]>

---------

Signed-off-by: Mitchell Gale <[email protected]>
Signed-off-by: Mitchell Gale <[email protected]>
Co-authored-by: Guian Gumpac <[email protected]>

Author: MitchellGale

build.gradle

@@ -86,7 +86,8 @@ spotless {
         target fileTree('.') {
             include 'common/**/*.java',
                     'datasources/**/*.java',
-                    'core/**/*.java'
+                    'core/**/*.java',
+                    'ppl/**/*.java'
             exclude '**/build/**', '**/build-*/**'
         }
         importOrder()