Update index.md

[lvthillo]

docker for mac is now officially supported by Docker 18.06.0 (Since I was struggling with the squash on a PR a new one..)

What this PR does / why we need it:

Which issue this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close that issue when PR gets merged): fixes #

Special notes for your reviewer:

[antoineco]

/lgtm
Sorry for the trouble with the previous squash :)

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: antoineco, lvthillo

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• OWNERS [antoineco]

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[codecov-io]

Codecov Report

Merging #2866 into master will increase coverage by 0.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master    #2866      +/-   ##
==========================================
+ Coverage   47.69%   47.71%   +0.01%     
==========================================
  Files          75       75              
  Lines        5434     5434              
==========================================
+ Hits         2592     2593       +1     
+ Misses       2512     2510       -2     
- Partials      330      331       +1

Impacted Files	Coverage Δ
internal/watch/file_watcher.go	84.61% <0%> (+3.84%)	⬆️

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