package/mongoose: bump to version 7.8

Update hash of license file (date and URL updated with
https://github.com/cesanta/mongoose/commit/aaf55b6da0d4687cf6aae40011d38d0485bf8b34
https://github.com/cesanta/mongoose/commit/f8c84ca6722dbc47027af309ba64eaac34c7cfe9)

https://github.com/cesanta/mongoose/releases/tag/7.8
https://github.com/cesanta/mongoose/releases/tag/7.7
https://github.com/cesanta/mongoose/releases/tag/7.6
https://github.com/cesanta/mongoose/releases/tag/7.5
https://github.com/cesanta/mongoose/releases/tag/7.4
https://github.com/cesanta/mongoose/releases/tag/7.3



Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>