Test that metadata is updated with update function

[adamtheturtle]

Fixes #1132

[codecov]

Codecov Report

Merging #1133 into master will not change coverage.
The diff coverage is 100%.

@@          Coverage Diff           @@
##           master   #1133   +/-   ##
======================================
  Coverage     100%    100%           
======================================
  Files          11      11           
  Lines         588     602   +14     
  Branches       14      14           
======================================
+ Hits          588     602   +14

Impacted Files	Coverage Δ
tests/test_vws.py	100% <100%> (ø)	⬆️

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