Fix: downgrade webdav to fix Filepicker

[hamza221]

Error :

Response in webdav lib:

code :
https://github.com/perry-mitchell/webdav-client/blob/129a9d031e0f07fd8cb6bfe8fa3d47cceeabe004/source/operations/stat.ts#L28

[st3iny]

Breaks here:

mail/src/dav/client.js

Lines 33 to 34 in d24f984

	const patcher = webdav.getPatcher()
	patcher.patch('request', axios)

Webdav switched to the fetch API internally and we still force it to use axios. Hence it breaks somewhere in the library as response.text() is not a function in axios.

[st3iny]

/backport to stable3.6