fix two typos in architecture.rst
fix two typos in architecture.rst

As title.

seibert/numba,IntelLabs/numba,stonebig/numba,stuartarchibald/numba,stonebig/numba,cpcloud/numba,cpcloud/numba,gmarkall/numba,IntelLabs/numba,numba/numba,stonebig/numba,numba/numba,numba/numba,IntelLabs/numba,numba/numba,gmarkall/numba,gmarkall/numba,stuartarchibald/numba,gmarkall/numba,IntelLabs/numba,cpcloud/numba,cpcloud/numba,seibert/numba,sklam/numba,numba/numba,sklam/numba,stuartarchibald/numba,sklam/numba,sklam/numba,seibert/numba,seibert/numba,gmarkall/numba,stonebig/numba,seibert/numba,sklam/numba,stuartarchibald/numba,IntelLabs/numba,stonebig/numba,stuartarchibald/numba,cpcloud/numba