Plug leak stemming from g_path_get_basename
This MR fixes an error when building with AddressSanitizer + LeakSanitizer:
Making all in xdt-csource
make[1]: Entering directory '/home/s/code/xfce4-dev-tools/xdt-csource'
CC xdt_csource-main.o
CCLD xdt-csource
make[1]: Leaving directory '/home/s/code/xfce4-dev-tools/xdt-csource'
Making all in tests
make[1]: Entering directory '/home/s/code/xfce4-dev-tools/tests'
../xdt-csource/xdt-csource --extern --build-list data_bin ./data/data.bin data_txt ./data/data.txt > test-xdt-csource-data.c
=================================================================
==4162==ERROR: LeakSanitizer: detected memory leaks
Direct leak of 12 byte(s) in 1 object(s) allocated from:
#0 0x5831dd56e279 in malloc (/home/s/code/xfce4-dev-tools/xdt-csource/xdt-csource+0x15c279) (BuildId: 9821e4bcb168934e)
#1 0x778ef55595ba in g_malloc (/usr/lib/libglib-2.0.so.0+0x625ba) (BuildId: 7abffba39dc59aa95290cbeb721e69fe4e3012fb)
#2 0x778ef55384b7 in g_path_get_basename (/usr/lib/libglib-2.0.so.0+0x414b7) (BuildId: 7abffba39dc59aa95290cbeb721e69fe4e3012fb)
#3 0x5831dd5b6d4a in main /home/s/code/xfce4-dev-tools/xdt-csource/main.c:355:18
#4 0x778ef5206c87 (/usr/lib/libc.so.6+0x25c87) (BuildId: 32a656aa5562eece8c59a585f5eacd6cf5e2307b)
#5 0x778ef5206d4b in __libc_start_main (/usr/lib/libc.so.6+0x25d4b) (BuildId: 32a656aa5562eece8c59a585f5eacd6cf5e2307b)
#6 0x5831dd482194 in _start (/home/s/code/xfce4-dev-tools/xdt-csource/xdt-csource+0x70194) (BuildId: 9821e4bcb168934e)
SUMMARY: AddressSanitizer: 12 byte(s) leaked in 1 allocation(s).
make[1]: *** [Makefile:1157: test-xdt-csource-data.c] Error 1
make[1]: Leaving directory '/home/s/code/xfce4-dev-tools/tests'
make: *** [Makefile:409: all-recursive] Error 1