gdb/testsuite: remove gdb.python/pretty-print-call-by-hand.exp

gdb/testsuite: remove gdb.python/pretty-print-call-by-hand.exp

This test was added without a corresponding fix, with some setup_kfails.
However, it results in UNRESOLVED results when GDB is built with ASan.

  ERROR: GDB process no longer exists
  GDB process exited with wait status 1946871 exp7 0 1
  UNRESOLVED: gdb.python/pretty-print-call-by-hand.exp: frame print: backtrace test (PRMS gdb/28856)

Remove the test from the tree, I'll attach it to the Bugzilla bug
instead [1].

[1] https://sourceware.org/bugzilla/show_bug.cgi?id=28856

Change-Id: Id95d8949fb8742874bd12aeac758aa4d7564d678