Updating Skype Client flatpak

• check out https://support.skype.com/en/faq/FA34778/release-notes-for-skype-for-windows-mac-linux-and-web for release notes for the latest version
• download latest snap using the link from this one-liner:

  curl -s -H 'Snap-Device-Series: 16' http://api.snapcraft.io/v2/snaps/info/skype | jq '."channel-map" | map(select(.channel.architecture == "amd64" and .channel.name == "stable")) | .[0].download.url'

• get size and SHA256 using sha256sum
• update com.skype.Client.json's last extra-data section with new URL, size and SHA256
• add a top <release> entry under <releases> to the com.skype.Client.appdata.xml (date attribute value comes from release notes above)
• commit, push & create a PR!