Fix bug in experimental conversion code.

src/pcre2_convert.c

@@ -284,7 +284,7 @@ while (plength > 0)
     break;  
 
     default:
-    if (c < 256 && strchr("\\{}?*+[]()|.^$", c) != NULL)
+    if (c < 256 && strchr("\\{}?*+[]()|", c) != NULL)
       {
       PUTCHARS(STR_BACKSLASH);
       }

testdata/testinput24

@@ -257,6 +257,10 @@
 \= Expect no match
     a1b
 
+/how.to/
+
+/^how to/
+
 #pattern convert=unset
 
 /abc/

testdata/testoutput24

@@ -411,6 +411,12 @@ a*b\+c+[def]\(ab\)(cd)
     a1b
 No match
 
+/how.to/
+how.to
+
+/^how to/
+^how to
+
 #pattern convert=unset
 
 /abc/