Update eclipse-mosquitto Docker tag to v2.0.18

[renovate]

This PR contains the following updates:

Package	Update	Change
eclipse-mosquitto	patch	2.0.17 -> 2.0.18

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Configuration

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[codecov]

Codecov Report

Merging #237 (4b4d487) into master (ee021c2) will not change coverage.
Report is 3 commits behind head on master.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #237   +/-   ##
=======================================
  Coverage   92.53%   92.53%           
=======================================
  Files          34       34           
  Lines        1915     1915           
=======================================
  Hits         1772     1772           
  Misses        123      123           
  Partials       20       20