docs: Update Quickstart and Tutorials pages with new Skaffold onboarding walkthrough

[maggieneterval]

Fixes: #8228

Description
Update Quickstart and Tutorials pages with new Skaffold onboarding walkthrough.

User facing changes

• Adds a new page to the Tutorials section that includes a link to open the new tutorial in Cloud Shell.
• Updates the Quickstart page to include the new tutorial text-only version and Cloud Shell link.

[maggieneterval]

@aaron-prindle PTAL 😄

[codecov]

Codecov Report

Merging #8274 (b709910) into main (290280e) will decrease coverage by 4.37%.
The diff coverage is 54.68%.

@@            Coverage Diff             @@
##             main    #8274      +/-   ##
==========================================
- Coverage   70.48%   66.10%   -4.38%     
==========================================
  Files         515      601      +86     
  Lines       23150    29492    +6342     
==========================================
+ Hits        16317    19496    +3179     
- Misses       5776     8533    +2757     
- Partials     1057     1463     +406     

Impacted Files	Coverage Δ
cmd/skaffold/app/cmd/completion.go	13.04% <0.00%> (-1.25%)	⬇️
cmd/skaffold/app/cmd/config/list.go	65.21% <ø> (ø)
cmd/skaffold/app/cmd/config/set.go	88.72% <ø> (ø)
cmd/skaffold/app/cmd/config/util.go	54.28% <ø> (ø)
cmd/skaffold/app/cmd/credits.go	100.00% <ø> (ø)
cmd/skaffold/app/cmd/credits/export.go	0.00% <0.00%> (ø)
cmd/skaffold/app/cmd/deploy.go	40.90% <0.00%> (-12.94%)	⬇️
cmd/skaffold/app/cmd/generate_pipeline.go	60.00% <ø> (ø)
cmd/skaffold/app/cmd/inspect_modules.go	65.00% <ø> (ø)
cmd/skaffold/app/cmd/inspect_profiles.go	66.66% <ø> (ø)
... and 405 more

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[container-tools-bot]

Please visit http://34.121.119.36:1313 to view changes to the docs.

[aaron-prindle]

Awesome, just looked loaded the preview of the changes and it looks great.

[aaron-prindle]

LGTM!