Fix pinning system on devel

[Menduist]

devel switched to new nimble, so the pinning system needs to be updated.

Now, the .pinned & nimble.lock need to be kept in sync, for more fun
Once we stop supporting nim versions with the old nimble, we'll be able to only use the nimble lock system

[codecov]

Codecov Report

Merging #820 (a09af50) into unstable (a17cad7) will increase coverage by 0.01%.
The diff coverage is n/a.

Additional details and impacted files

@@             Coverage Diff              @@
##           unstable     #820      +/-   ##
============================================
+ Coverage     83.62%   83.63%   +0.01%     
============================================
  Files            81       81              
  Lines         14726    14726              
============================================
+ Hits          12314    12316       +2     
+ Misses         2412     2410       -2     

Impacted Files	Coverage Δ
libp2p/protocols/secure/secure.nim	71.15% <0.00%> (-3.85%)	⬇️
libp2p/muxers/mplex/mplex.nim	88.23% <0.00%> (-0.85%)	⬇️
libp2p/crypto/rsa.nim	79.18% <0.00%> (-0.20%)	⬇️
libp2p/transports/wstransport.nim	85.26% <0.00%> (ø)
libp2p/protocols/pubsub/pubsubpeer.nim	87.87% <0.00%> (+2.27%)	⬆️
libp2p/muxers/mplex/lpchannel.nim	86.74% <0.00%> (+3.01%)	⬆️