Use autoCopy when copying vector blocks

This way, types that implement AutonomousValue can specify into what
type they are copied. This can be applied e.g. for proxy types such as
the BlockVectorWindow used in ISTL's VariableBlockVector.

For types that do not implement AutonomousValue, the behavior should
not change.
2 jobs for feature/use_autocopy in 3 minutes and 25 seconds (queued for 1 second)
latest
Status Name Job ID Coverage
  Test
passed dune:git clang C++17 #95228

00:03:25

passed dune:git gcc-8 C++17 #95229

00:02:15