Bump rubygem-ffi to 1.16.3

[joshcooper]

Bump ffi to 1.16.3 in agent-runtime-main

This needs to be updated in three places because of the precompiled binaries for windows x64 and x86:

puppet-runtime/configs/components/rubygem-ffi.rb

Line 15 in acf6917

pkg.sha256sum '6f2ed2fa68047962d6072b964420cba91d82ce6fa8ee251950c17fca6af3c2a0'

puppet-runtime/configs/components/rubygem-ffi.rb

Line 63 in acf6917

pkg.sha256sum '9acc4e474bef25dbcf827b1e6fce4067e9a1eff74a0296d25f0af392fafcd096'

puppet-runtime/configs/components/rubygem-ffi.rb

Line 74 in acf6917

pkg.sha256sum '6e52c39fdbbccc085ae05d489d1b835ce05dcdf2a4c88ba739e3b42afd2b5404'

This is blocked on:

• Accept ffi >= 1.16.3, < 1.17.0 puppet#9330
• (FACT-3434) Accept ffi >= 1.16.3, < 1.17.0 facter#2707
• [Backport 7.x] (FACT-3434) Accept ffi >= 1.16.3, < 1.17.0 puppet#9342