Merge branch 'patch-2' into 'master'

Update troubleshooting.md

See merge request !555
5 jobs for <span class="ref-name">419-upgrade-version-of-elasticsearch-that-we-install-to-either-5-6-or-6-x</span> in 19 minutes and 42 seconds (queued for 1 second)
Status Job ID Name Coverage
  Build
manual #127558843
allowed to fail manual
build:image
 
  Test
passed #127558844
allowed to fail
code_quality

00:05:01

passed #127558845
allowed to fail
container_scanning

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passed #127558846
test:install

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passed #127558847
test:update

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