[gimp] build: no need to chmod the test file which is already executable.

[Jehan <jehanp src gnome org>]

commit 201cbe7e3eeed87170c06c3a79b039009473522b
Author: Jehan <jehan girinstud io>
Date:   Wed Dec 22 17:13:07 2021 +0100

    build: no need to chmod the test file which is already executable.
    
    Also when working on out-of-tree builds, it would not find the file
    anyway and we get this output:
    
    > chmod: cannot access 'test-installer-langs.sh': No such file or directory
    
    Though this was not breaking the tests, it has clearly been useless
    until we see this one today.

 build/windows/installer/lang/Makefile.am | 1 -
 1 file changed, 1 deletion(-)
---
diff --git a/build/windows/installer/lang/Makefile.am b/build/windows/installer/lang/Makefile.am
index 7d7c2a9c0b..e8e4d56a63 100644
--- a/build/windows/installer/lang/Makefile.am
+++ b/build/windows/installer/lang/Makefile.am
@@ -74,7 +74,6 @@ clean-local:
        done
 
 TESTS_ENVIRONMENT = \
-       chmod +x test-installer-langs.sh; \
        GIMP_TESTING_ABS_TOP_SRCDIR=@abs_top_srcdir@
 
 TESTS = test-installer-langs.sh