Concatenate character tokens

Looks like these few places were missed when ParseError token type was removed.

This PR fixes them to restore the state promised in the README:

> All adjacent character tokens are coalesced into a single ["Character", data] token.

Author: RReverser

tokenizer/test2.test

@@ -195,7 +195,7 @@
 
 {"description":"Unescaped <",
 "input":"foo < bar",
-"output":[["Character", "foo "], ["Character", "< bar"]],
+"output":[["Character", "foo < bar"]],
 "errors":[
     { "code": "invalid-first-character-of-tag-name", "line": 1, "col": 6 }
 ]},
@@ -242,7 +242,7 @@
 
 {"description":"Empty end tag with following characters",
 "input":"a</>bc",
-"output":[["Character", "a"], ["Character", "bc"]],
+"output":[["Character", "abc"]],
 "errors":[
     { "code": "missing-end-tag-name", "line": 1, "col": 4 }
 ]},

tokenizer/test3.test

@@ -8415,7 +8415,7 @@
 
 {"description":"<<",
 "input":"<<",
-"output":[["Character", "<"], ["Character", "<"]],
+"output":[["Character", "<<"]],
 "errors":[
     { "code": "invalid-first-character-of-tag-name", "line": 1, "col": 2 },
     { "code": "eof-before-tag-name", "line": 1, "col": 3 }

tokenizer/unicodeCharsProblematic.test

@@ -18,7 +18,7 @@
 {"description": "Invalid Unicode character U+DFFF with valid preceding character",
 "doubleEscaped":true,
 "input": "a\\uDFFF",
-"output":[["Character", "a"], ["Character", "\\uDFFF"]],
+"output":[["Character", "a\\uDFFF"]],
 "errors":[
     { "code": "surrogate-in-input-stream", "line": 1, "col": 2 }
 ]},