Fix atomicwrapper Swap panic

[eNV25]

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• updated the changelog if the change is user-facing;
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[codecov]

Codecov Report

Merging #128 (18c2311) into master (78a3b8e) will decrease coverage by 0.43%.
The diff coverage is 66.66%.

@@             Coverage Diff             @@
##            master     #128      +/-   ##
===========================================
- Coverage   100.00%   99.57%   -0.43%     
===========================================
  Files           23       23              
  Lines          232      234       +2     
===========================================
+ Hits           232      233       +1     
- Misses           0        1       +1     

Impacted Files	Coverage Δ
bool.go	100.00% <ø> (ø)
duration.go	100.00% <ø> (ø)
error.go	100.00% <ø> (ø)
float32.go	100.00% <ø> (ø)
float64.go	100.00% <ø> (ø)
int32.go	100.00% <ø> (ø)
int64.go	100.00% <ø> (ø)
time.go	100.00% <ø> (ø)
uint32.go	100.00% <ø> (ø)
uint64.go	100.00% <ø> (ø)
... and 2 more

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[eNV25]

Fixes #126

[eNV25]

Closing because #130