Fix typo; recieved -> received

[joakimnordling]

Summary

When following along the tutorial I noticed a typo that I wanted to fix (recieved -> received).

Requirements (place an x in each [ ])

• I've read and understood the Contributing Guidelines and have done my best effort to follow them.
• I've read and agree to the Code of Conduct.

[codecov]

Codecov Report

Merging #478 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #478   +/-   ##
=======================================
  Coverage   69.58%   69.58%           
=======================================
  Files          15       15           
  Lines        1654     1654           
  Branches       91       91           
=======================================
  Hits         1151     1151           
  Misses        481      481           
  Partials       22       22

Impacted Files	Coverage Δ
slack/rtm/client.py	84.15% <ø> (ø)	⬆️

---

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Δ = absolute <relative> (impact), ø = not affected, ? = missing data
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[codecov]

Codecov Report

Merging #478 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #478   +/-   ##
=======================================
  Coverage   69.58%   69.58%           
=======================================
  Files          15       15           
  Lines        1654     1654           
  Branches       91       91           
=======================================
  Hits         1151     1151           
  Misses        481      481           
  Partials       22       22

Impacted Files	Coverage Δ
slack/rtm/client.py	84.15% <ø> (ø)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update df5351f...0d33aa0. Read the comment docs.

[clavin]

👍 Nice catch!