Use npm ci instead of npm install

[tpmccallum]

Signed-off-by: tpmccallum tim.mccallum@fermyon.com Content must go through a pre-merge checklist.

Fixes https://github.com/fermyon/developer/issues/922

Pre-Merge Content Checklist

This documentation has been checked to ensure that:

• [x] The title, template, and date are all set
• [x] Does this PR have a new menu item (anywhere in templates/*.hbs files) that points to a document .md that is set to publish in the future? If so please only publish the .md and .hbs changes in real-time (otherwise there will be a menu item pointing to a .md file that does not exist)
• [x] File does not use CRLF, but uses plain LF (hint: use cat -ve <filename> | grep $'\r' | wc -l and expect 0 as a result)
• [x] Has passed bart check
• [x] Has been manually tested by running in Spin/Bartholomew (hint: use PREVIEW_MODE=1 and run npm run styles to update styling)
• [x] Headings are using Title Case
• [x] Code blocks have the programming language set to properly highlight syntax and the proper copy directive
• [x] Have tested with npm run test and resolved all errors
• [x] Relates to an existing (potentially outdated) blog article? If so please add URL in blog to point to this content.

[github-actions[bot]]

🚀 preview deployed successfully to Fermyon Cloud and available at https://fermyon-developer-pr-1283-g6atov7i.fermyon.app

[tpmccallum]

Also, as this PR I just checked that we can do the following and local preview:

$ cd spin-up-hub/
$ npm ci
$ cd ../
$ npm ci
$ spin build
$ spin up -e PREVIEW_MODE=1

All worked a treat!

Then when I went ahead and performed git add and git commit there were no redundant file, which is perfect.

$ git add .
$ git commit -S --signoff -m "Should not create files"
On branch tpmccallum-patch-43
Your branch is up to date with 'origin/tpmccallum-patch-43'.
nothing to commit, working tree clean