renamed "stringtype" to "string_type"

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

@@ -1998,7 +1998,7 @@ class UnknownType extends Type, @unknowntype { }
 /**
  * The predefined `string` type.
  */
-class StringType extends Type, @stringtype { }
+class StringType extends Type, @string_type { }
 
 /**
  * The predefined `number` type.

javascript/ql/src/semmlecode.javascript.dbscheme

@@ -613,7 +613,7 @@ type_child (
 
 case @type.kind of
   0 = @any_type
-| 1 = @stringtype
+| 1 = @string_type
 | 2 = @numbertype
 | 3 = @uniontype
 | 4 = @truetype

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

@@ -910,7 +910,7 @@
 <v>1</v>
 </e>
 <e>
-<k>@stringtype</k>
+<k>@string_type</k>
 <v>1</v>
 </e>
 <e>