glsl/tests: suffix .sh/.py files as applicable

This makes it easier/clearer as to:
 - if the file should have the execute bit set (.py should not)
 - do we need the shebang in the first place and if so what it should be

Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
Reviewed-by: Eric Engestrom <eric.engestrom@imgtec.com>

src/compiler/glsl/glcpp/tests/glcpp-test-cr-lf.sh

@@ -7,10 +7,10 @@
 
 if [ ! -z "$srcdir" ]; then
    testdir="$srcdir/glsl/glcpp/tests"
-   glcpp_test="$srcdir/glsl/glcpp/tests/glcpp-test"
+   glcpp_test="$srcdir/glsl/glcpp/tests/glcpp-test.sh"
 else
    testdir=.
-   glcpp_test=./glcpp-test
+   glcpp_test=./glcpp-test.sh
 fi
 
 total=0