Generic/[Lower|Upper]CaseConstant: add tests with FQN true/false/null

These are the only two sniffs explicitly targetting `true`, `false` and `null`.

This commit adds some tests to safeguard these sniffs function correctly on "fully qualified true/false/null".

Author: jrfnl

src/Standards/Generic/Tests/PHP/LowerCaseConstantUnitTest.1.inc

@@ -177,3 +177,7 @@ abstract class SkipOverPHP84AbstractProperties {
     abstract MyType|TRUE $propA {get;}
     protected abstract NULL|MyClass $propB {set;}
 }
+
+$a = \NULL;
+$a = \falSe;
+$a = \True;

src/Standards/Generic/Tests/PHP/LowerCaseConstantUnitTest.1.inc.fixed

@@ -177,3 +177,7 @@ abstract class SkipOverPHP84AbstractProperties {
     abstract MyType|TRUE $propA {get;}
     protected abstract NULL|MyClass $propB {set;}
 }
+
+$a = \null;
+$a = \false;
+$a = \true;

src/Standards/Generic/Tests/PHP/LowerCaseConstantUnitTest.php

@@ -70,6 +70,9 @@ public function getErrorList($testFile='')
                 169 => 1,
                 171 => 1,
                 173 => 1,
+                181 => 1,
+                182 => 1,
+                183 => 1,
             ];
 
         case 'LowerCaseConstantUnitTest.js':

src/Standards/Generic/Tests/PHP/UpperCaseConstantUnitTest.inc

@@ -118,3 +118,7 @@ abstract class SkipOverPHP84AbstractProperties {
     abstract MyType|true $propA {get;}
     protected abstract null|MyClass $propB {set;}
 }
+
+$a = \null;
+$a = \falSe;
+$a = \True;

src/Standards/Generic/Tests/PHP/UpperCaseConstantUnitTest.inc.fixed

@@ -118,3 +118,7 @@ abstract class SkipOverPHP84AbstractProperties {
     abstract MyType|true $propA {get;}
     protected abstract null|MyClass $propB {set;}
 }
+
+$a = \NULL;
+$a = \FALSE;
+$a = \TRUE;

src/Standards/Generic/Tests/PHP/UpperCaseConstantUnitTest.php

@@ -55,6 +55,9 @@ public function getErrorList()
             112 => 1,
             113 => 1,
             114 => 1,
+            122 => 1,
+            123 => 1,
+            124 => 1,
         ];
 
     }//end getErrorList()