[libvtrutil][CMake] Updated Deprecated exec_program

There were some CMake warnings during compile-time which were
complaining about exec_program being deprecated. Replaced with
execute_process which is a more verbose command to use anyways.

Author: AlexandreSinger

libs/libvtrutil/cmake/modules/configure_version.cmake

@@ -4,10 +4,11 @@
 #Figure out the git revision
 find_package(Git QUIET)
 if(GIT_FOUND)
-    exec_program(${GIT_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}
-                 ARGS describe --always --long --dirty
-                 OUTPUT_VARIABLE VTR_VCS_REVISION
-                 RETURN_VALUE GIT_DESCRIBE_RETURN_VALUE)
+    execute_process(COMMAND ${GIT_EXECUTABLE} describe --always --long --dirty
+                    WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
+                    OUTPUT_VARIABLE VTR_VCS_REVISION
+                    OUTPUT_STRIP_TRAILING_WHITESPACE
+                    RESULT_VARIABLE GIT_DESCRIBE_RETURN_VALUE)
 
     if(NOT GIT_DESCRIBE_RETURN_VALUE EQUAL 0)
         #Git describe failed, usually this means we
@@ -18,10 +19,12 @@ if(GIT_FOUND)
 
     #Call again with exclude to get the revision excluding any tags
     #(i.e. just the commit ID and dirty flag)
-    exec_program(${GIT_EXECUTABLE} ${CMAKE_CURRENT_SOURCE_DIR}
-                 ARGS describe --always --long --dirty --exclude '*'
-                 OUTPUT_VARIABLE VTR_VCS_REVISION_SHORT
-                 RETURN_VALUE GIT_DESCRIBE_RETURN_VALUE)
+    execute_process(COMMAND ${GIT_EXECUTABLE} describe --always --long --dirty --exclude '*'
+                    WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
+                    OUTPUT_VARIABLE VTR_VCS_REVISION_SHORT
+                    OUTPUT_STRIP_TRAILING_WHITESPACE
+                    RESULT_VARIABLE GIT_DESCRIBE_RETURN_VALUE)
+
     if(NOT GIT_DESCRIBE_RETURN_VALUE EQUAL 0)
         #Git describe failed, usually this means we
         #aren't in a git repo -- so don't set a VCS