package/go: security bump to version 1.16.7

go1.16.7 (released 2021-08-05) includes a security fix to the
net/http/httputil package, as well as bug fixes to the compiler, the
linker, the runtime, the go command, and the net/http package.

https://golang.org/doc/devel/release#go1.16



Signed-off-by: Christian Stewart <christian@paral.in>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>