docs(troubleshooting.md): Update running on Alpine example

[sergiitk]

Refreshes "Running on Alpine":

• Use latest LTS Node 10 on alpine in the example
• The newest Chromium package supported on Alpine @edge channel is now 71
• Puppeteer corresponding to Chromium 71 is v1.9.0
• harfbuzz is now required by dynamic linking, Ref hb_font_set_variations: symbol not found #3019

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[sergiitk]

I signed it!

[googlebot]

CLAs look good, thanks!

[sergiitk]

Just for some context: I was setting up Puppeteer in Docker for my project and had to fix a couple of things in the example to make it work. Looks like other people (f.e. #3019) had to jump over the same hoops, so I've decided to capture the working setup in the example.

[aslushnikov]

Awesome, thanks!

[sergiitk]

Glad I could help!