[Enhancement] Add deactivate SSL certification verity option

[kim3321]

Enables to disable ssl certificate checking

Motivation

Add the option not to check ssl certificate to allow downloads to be performed in environments where ssl errors occur (for example, on-premises)

Modification

Some codes have been modified so that the requests module can select whether to check the ssl certificate or not module.

Use cases

mim download mmcls --no-check-certificate --config resnet18_8xb16_cifar10 --dest .

[ice-tong]

Hi @kim3321 , sorry for the late reply. ^_^

This changes looks grate to me, thanks for your contribution!

[ice-tong]

LGTM, thanks!

[zhouzaida]

Hi, the lint failed.

[openmmlab-bot]

Dear kim3321,
First of all, we want to express our gratitude for your significant PR in the MIM project. Your contribution is highly appreciated, and we are grateful for your efforts in helping improve this open-source project during your personal time. We believe that many developers will benefit from your PR.
We are looking forward to continuing our collaboration with you. OpenMMLab has established a special contributors' organization called MMSIG, which provides contributors with open-source certificates, a recognition system, and exclusive rewards. You can contact us by adding our WeChat（if you have WeChat): openmmlabwx, or join in our discord：https://discord.gg/raweFPmdzG. We sincerely hope you will join us!
Best regards！ @kim3321