renamed "undefinedtype" to "undefined_type"

javascript/ql/src/semmle/javascript/TypeScript.qll

@@ -2124,7 +2124,7 @@ class VoidType extends Type, @void_type { }
 /**
  * The `undefined` type.
  */
-class UndefinedType extends Type, @undefinedtype { }
+class UndefinedType extends Type, @undefined_type { }
 
 /**
  * The `null` type.

javascript/ql/src/semmlecode.javascript.dbscheme

@@ -623,7 +623,7 @@ case @type.kind of
 | 8 = @canonical_type_variable_type
 | 9 = @typeof_type
 | 10 = @void_type
-| 11 = @undefinedtype
+| 11 = @undefined_type
 | 12 = @nulltype
 | 13 = @nevertype
 | 14 = @plainsymboltype

javascript/ql/src/semmlecode.javascript.dbscheme.stats

@@ -950,7 +950,7 @@
 <v>1</v>
 </e>
 <e>
-<k>@undefinedtype</k>
+<k>@undefined_type</k>
 <v>1</v>
 </e>
 <e>