Refining code from rabbit suggestions

Author: cvvergara

include/c_common/e_report.h

@@ -93,7 +93,7 @@ pgr_global_report(char**, char**, char**);
  *  ~~~~
  */
 void
-pgr_print_notice(char*);
+pgr_print_notice(const char*);
 
 /* @brief throws postgres error when first string is not null */
 void pgr_throw_error(const char*, const char*);

src/common/e_report.c

@@ -44,7 +44,7 @@ pgr_throw_error(const char *err, const char *hint) {
  * @param[in] msg string to send notice to PostgreSQL
  */
 void
-pgr_print_notice(char* msg) {
+pgr_print_notice(const char* msg) {
     ereport(NOTICE, (errmsg_internal("%s", msg)));
 }