lldb-std-vector-prettyprint: Update lldb output

lldb started to print the type used in the template.

lldb-std-vector-prettyprint/test.sh

@@ -5,7 +5,7 @@ g++ -g test.cpp
 lldb -b -o 'breakpoint set --file test.cpp --line 7' -o run -o 'p v' -- a.out | tee lldb.log
 
 test `grep \
-    -e '(std::vector<int, std::allocator<> >) $0 = size=1 {' \
+    -e '(std::vector<int, std::allocator<\(int\)\?> >) $0 = size=1 {' \
     -e '\[0\] = 2' \
     lldb.log \
   | wc -l` -eq 2