Rclone needs update to v1.64.0

[fridgewidget]

Hi, just so you know, the Rclone-mac formula needs updating to upstream version v1.64.0, released earlier this month. This doesn't appear to be a major update, but Kapitainsky's Rclone Browser (https://kapitainsky.github.io/RcloneBrowser/) keeps bugging me about my outdated Rclone version. 🙄

If you don't have the time and/or energy to do it, or would like some help, I could probably learn to do it myself and submit it (I have a MacBook Air M1 with all the development tools), though maintaining Homebrew builds isn't my area of expertise and I might need a little help to get started.

Thanks!