This patch fixes a think-o in gdb.base/paginate-bg-execution.exp -- 
there are two calls to gdb_test with only a single argument.  Looking at 
the definition of this proc in lib/gdb.exp, the second argument (the 
output pattern) is not supposed to be optional.  For whatever reason, I 
was only seeing failures on remote Windows host testing, but it must 
have been an accident that it appeared to be working elsewhere.

I copied the breakpoint output pattern used elsewhere in the testsuite, 
and confirmed this passes now.  OK to commit?

-Sandra