meson: use gtest protocol for gtest based tests when possible

With the `gtest` protocol meson will add some extra arguments to the
test to generate better junit results, which may be useful. This
protocol is only available in meson 0.55.0+, so keep using the default
`exitcode` protocol for meson older than that.

Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/8484>

src/compiler/glsl/tests/meson.build

@@ -33,6 +33,7 @@ test(
     dependencies : [dep_clock, dep_thread, idep_gtest, idep_mesautil],
   ),
   suite : ['compiler', 'glsl'],
+  protocol : gtest_test_protocol,
 )
 
 test(
@@ -49,6 +50,7 @@ test(
     dependencies : [dep_thread, idep_gtest, idep_mesautil],
   ),
   suite : ['compiler', 'glsl'],
+  protocol : gtest_test_protocol,
 )
 
 test(
@@ -63,6 +65,7 @@ test(
     dependencies : [dep_thread, idep_gtest, idep_mesautil],
   ),
   suite : ['compiler', 'glsl'],
+  protocol : gtest_test_protocol,
 )
 
 test(
@@ -77,6 +80,7 @@ test(
     dependencies : [dep_thread, idep_gtest],
   ),
   suite : ['compiler', 'glsl'],
+  protocol : gtest_test_protocol,
 )
 
 # Meson can't auto-skip these on cross builds because of the python wrapper