Fix sed -i compatibility on macOS in configure (#1598)

macOS BSD sed requires an explicit empty string argument after
-i (sed -i '' 'script' file), unlike GNU sed which takes -i
without a suffix argument. Without this fix, BSD sed misinterprets
the sed script as a backup suffix and treats the filename as the
script, causing "unterminated substitute pattern" error.

Author: zhangyue1818

configure

@@ -24833,4 +24833,11 @@ fi
 # The configure args contain '-Wl,-rpath,\$$ORIGIN`, when it falls
 # as a C literal string, it's invalid, so converting `\` to `\\`
 # to be correct for C program.
-sed -i '/define CONFIGURE_ARGS/s,\([^\\]\)\\\$\$,\1\\\\$$,g' src/include/pg_config.h
+case $build_os in
+darwin*)
+  sed -i '' '/define CONFIGURE_ARGS/s,\([^\\]\)\\\$\$,\1\\\\$$,g' src/include/pg_config.h
+  ;;
+*)
+  sed -i '/define CONFIGURE_ARGS/s,\([^\\]\)\\\$\$,\1\\\\$$,g' src/include/pg_config.h
+  ;;
+esac