fix  some error (#367)
fix  some error (#367)

* fix some error in aws.md

* fix error in buy-gpu.md

* fix error in hybridize.md

* Update aws.md

mli/gluon-tutorials-zh,d2l-ai/d2l-zh,mli/gluon-tutorials-zh,mli/gluon-tutorials-zh,d2l-ai/d2l-zh,mli/gluon-tutorials-zh,d2l-ai/d2l-zh