fix outdated pcre2.h (pcre2.h.generic)

Author: mvorisek

ext/pcre/pcre2lib/pcre2.h

@@ -324,7 +324,7 @@ pcre2_pattern_convert(). */
 #define PCRE2_ERROR_ALPHA_ASSERTION_UNKNOWN        195
 #define PCRE2_ERROR_SCRIPT_RUN_NOT_AVAILABLE       196
 #define PCRE2_ERROR_TOO_MANY_CAPTURES              197
-#define PCRE2_ERROR_CONDITION_ATOMIC_ASSERTION_EXPECTED  198
+#define PCRE2_ERROR_MISSING_OCTAL_DIGIT            198
 #define PCRE2_ERROR_BACKSLASH_K_IN_LOOKAROUND      199
 #define PCRE2_ERROR_MAX_VAR_LOOKBEHIND_EXCEEDED    200
 #define PCRE2_ERROR_PATTERN_COMPILED_SIZE_TOO_BIG  201