Upgrade hubcaps to v0.7.0

[BrainBuzzer]

Hi, I've been interested to use hubcaps in my project, but since it uses tokio v1.17, while the current published version on crates.io uses v0.2, hubcaps won't work properly. I saw that commit for upgrading tokio to v~1 has been added over a year ago, but crates.io one uses v0.2.