minor typos in docs

[howardosborne]

seen these things too many times :-)

[codecov]

Codecov Report

Merging #1453 into master will decrease coverage by 0.04%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #1453      +/-   ##
==========================================
- Coverage   81.30%   81.26%   -0.05%     
==========================================
  Files          27       27              
  Lines        2359     2359              
  Branches      363      363              
==========================================
- Hits         1918     1917       -1     
  Misses        350      350              
- Partials       91       92       +1     

Impacted Files	Coverage Δ
locust/user/task.py	95.67% <0.00%> (-0.55%)	⬇️

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[cyberw]

Thanks :)