Update installation.md

[SonyaCode]

Fixes #3446

Changes:

• Added a sentence about how to check the node version
• Fixes incorrect numbering from Step 10

I have verified that this pull request:

• has no linting errors (npm run lint)
• has no test errors (npm run test)
• is from a uniquely-named feature branch and is up to date with the develop branch.
• is descriptively named and links to an issue number, i.e. Fixes #123

[welcome]

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[raclim]

Thanks so much for opening this issue and catching this fix! @SonyaCode