tests: Fix literal strings

This was done a while ago, to make MSVC happier as it doesn't like
non-ascii strings in C code.

(Or at least, that was the case at the time. This was almost 5 years ago
after all…)

    commit 273d280
    Author: Linquize <linquize@yahoo.com.hk>
    Date:   Thu Oct 17 21:20:36 2013 +0800

        Do not write Chinese literal strings directly

        MSVC does not encoding Chinese literal strings as UTF-8

However, for some reason the backslashes got escaped in this file (and
only in this file), and we missed it on code review.

tests/test_cangjiecharlist.c

@@ -28,7 +28,7 @@ void test_cangjie_char_list_append() {
     /* Append the first node */
     CangjieChar *char1;
     CangjieChar *char2;
-    int ret = cangjie_char_new(&char1, "\\xE6\\xA3\\xAE", "\\xE6\\xA3\\xAE",
+    int ret = cangjie_char_new(&char1, "\xE6\xA3\xAE", "\xE6\xA3\xAE",
                                "ddd", 123); // 森
     assert(ret == CANGJIE_OK);
 
@@ -38,7 +38,7 @@ void test_cangjie_char_list_append() {
     assert(l->c == char1);
 
     /* Append a new node */
-    ret = cangjie_char_new(&char2, "\\xE6\\x98\\x8E", "\\xE6\\x98\\x8E",
+    ret = cangjie_char_new(&char2, "\xE6\x98\x8E", "\xE6\x98\x8E",
                            "ab", 123); // 明
     assert(ret == CANGJIE_OK);
 
@@ -57,7 +57,7 @@ void test_cangjie_char_list_prepend() {
     /* Prepend the first node */
     CangjieChar *char1;
     CangjieChar *char2;
-    int ret = cangjie_char_new(&char1, "\\xE6\\x9B\\x9D", "\\xE6\\x9B\\x9D",
+    int ret = cangjie_char_new(&char1, "\xE6\x9B\x9D", "\xE6\x9B\x9D",
                                "aate", 123); // 曝
     assert(ret == CANGJIE_OK);
 
@@ -67,7 +67,7 @@ void test_cangjie_char_list_prepend() {
     assert(l->c == char1);
 
     /* Prepend a new node */
-    ret = cangjie_char_new(&char2, "\\xE9\\xB7\\xB3", "\\xE9\\xB9\\x87",
+    ret = cangjie_char_new(&char2, "\xE9\xB7\xB3", "\xE9\xB9\x87",
                            "abhaf", 123); // 鷳 / 鹇
     assert(ret == CANGJIE_OK);