fix: Change color of "Order" button on registration events

[divyamtayal]

Fixes #7817

Short description of what this resolves:

The order now button on registration events has an usual color. Please change it to the blue color which is used on other buttons.

Screenshots

Before	After

Checklist

• I have read the Contribution & Best practices Guide.
• My branch is up-to-date with the Upstream development branch.
• The acceptance, integration, unit tests and linter pass locally with my changes
• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation (if appropriate)

[vercel]

This pull request is being automatically deployed with Vercel (learn more).
To see the status of your deployment, click below or on the icon next to each commit.

🔍 Inspect: https://vercel.com/eventyay/open-event-frontend/EdXEnjCQ57RDDJafGnSmrG9zqBSS
✅ Preview: https://open-event-frontend-git-fork-daretobedifferent1-d0a6e5-eventyay.vercel.app

[codecov]

Codecov Report

Merging #7818 (2bcb4a6) into development (961275e) will increase coverage by 0.04%.
The diff coverage is n/a.

@@               Coverage Diff               @@
##           development    #7818      +/-   ##
===============================================
+ Coverage        18.57%   18.61%   +0.04%     
===============================================
  Files              613      613              
  Lines             7198     7198              
  Branches           149      149              
===============================================
+ Hits              1337     1340       +3     
+ Misses            5834     5831       -3     
  Partials            27       27              

Impacted Files	Coverage Δ
app/components/tabbed-navigation.js	53.33% <0.00%> (+20.00%)	⬆️

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 961275e...2bcb4a6. Read the comment docs.