[wpiutil,glass,dlt] Replace libprotobuf with upb for dynamic decode (#7988)

libprotobuf is a very annoying dependency to deal with, and with the switch to nanopb for generated C++ code, libprotobuf is only used for dynamic decode in the GUI apps. libprotobuf has been swapped out with upb, a much smaller C-based library that supports reflection and can therefore do dynamic decode. This means we can remove the libprotobuf dependency and stop dealing with build issues because of it.

docs/build.gradle

@@ -145,10 +145,9 @@ doxygen.sourceSets.main {
 
     exclude '*.pb.h'
 
-    // Save space by excluding protobuf and eigen
+    // Save space by excluding eigen
     exclude 'Eigen/**'
     exclude 'unsupported/**'
-    exclude 'google/protobuf/**'
 
     exclude '**/.clang-tidy'
     exclude '**/.clang-format'