advapi32/tests: Constify some character strings.

dlls/advapi32/tests/cred.c

@@ -563,8 +563,8 @@ static void test_CredMarshalCredentialA(void)
 
 static void test_CredUnmarshalCredentialA(void)
 {
-    static WCHAR tW[] = {'t',0};
-    static WCHAR testW[] = {'t','e','s','t',0};
+    static const WCHAR tW[] = {'t',0};
+    static const WCHAR testW[] = {'t','e','s','t',0};
     CERT_CREDENTIAL_INFO *cert;
     USERNAME_TARGET_CREDENTIAL_INFO *username;
     CRED_MARSHAL_TYPE type;

dlls/advapi32/tests/registry.c

@@ -1665,7 +1665,7 @@ static void test_rw_order(void)
 {
     HKEY hKey;
     DWORD dw = 0;
-    static char keyname[] = "test_rw_order";
+    static const char keyname[] = "test_rw_order";
     char value_buf[2];
     DWORD values, value_len, value_name_max_len;
     LSTATUS ret;