Add exceptions to files_same

This commit adds exceptions to the `files_same` function in the pkg_editor unit tests.

Previously, the tests would pass even if one of the files passed into `files_same` did not exist. By adding exceptions, we correctly error out if one of the files did not exist.

Author: IlanTruanovsky

lib/pkg_editor/test/pkg_editor_test.cpp

@@ -382,6 +382,8 @@ TEST(package, pack) {
 static bool files_same(const char *f1, const char *f2) {
   std::ifstream file1(f1, std::ifstream::ate | std::ifstream::binary);
   std::ifstream file2(f2, std::ifstream::ate | std::ifstream::binary);
+  file1.exceptions(std::ifstream::failbit | std::ifstream::badbit);
+  file2.exceptions(std::ifstream::failbit | std::ifstream::badbit);
   const std::ifstream::pos_type fileSize = file1.tellg();
 
   if (fileSize != file2.tellg()) {