Added additional to the UnexpectedEnd decode error

[VictorKoenders]

Closes #521

[codecov]

Codecov Report

Merging #522 (e4b6b79) into trunk (dadf335) will decrease coverage by 0.05%.
The diff coverage is 25.00%.

@@            Coverage Diff             @@
##            trunk     #522      +/-   ##
==========================================
- Coverage   71.08%   71.02%   -0.06%     
==========================================
  Files          47       47              
  Lines        3178     3182       +4     
==========================================
+ Hits         2259     2260       +1     
- Misses        919      922       +3     

Impacted Files	Coverage Δ
src/error.rs	0.00% <ø> (ø)
src/features/impl_std.rs	79.64% <0.00%> (-0.97%)	⬇️
src/varint/decode_unsigned.rs	69.41% <ø> (ø)
src/de/read.rs	68.96% <50.00%> (-1.41%)	⬇️

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[aviramha]

Thank you!!!