make DeprecationWarnings errors in doctests as well
make DeprecationWarnings errors in doctests as well

sampadsaha5/sympy,drufat/sympy,skidzo/sympy,kaushik94/sympy,madan96/sympy,chaffra/sympy,chaffra/sympy,drufat/sympy,kaushik94/sympy,souravsingh/sympy,skidzo/sympy,aktech/sympy,postvakje/sympy,madan96/sympy,jaimahajan1997/sympy,souravsingh/sympy,yashsharan/sympy,drufat/sympy,yashsharan/sympy,aktech/sympy,sampadsaha5/sympy,souravsingh/sympy,kaushik94/sympy,aktech/sympy,sampadsaha5/sympy,skidzo/sympy,jaimahajan1997/sympy,yashsharan/sympy,postvakje/sympy,madan96/sympy,postvakje/sympy,jaimahajan1997/sympy,chaffra/sympy