implemented the new design navbar

[ShravaniAK]

current navbar :

I have changed the following,

1. added border-radius to the search,
2. added border-radius to the corners of the tabs items,
3. Shifted the git source icons to the left

[netlify[bot]]

✅ Deploy Preview for knative ready!

Built without sensitive environment variables

Name	Link
🔨 Latest commit	5100f72143aa99d1a053c4856d4bbdbaf4cdb597
🔍 Latest deploy log	https://app.netlify.com/sites/knative/deploys/667958f25638870008c2053a
😎 Deploy Preview	https://deploy-preview-5965--knative.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify site configuration.

[Cali0707]

/cc @mmejia02 @zainabhusain227

Can the two of you check the preview and make sure it matches the designs?

[zainabhusain227]

Hey @ShravaniAK, where is the knative version number? I don't see it in the revised version. Besides that the rounded corners look good to me!

[knative-prow[bot]]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: Cali0707, ShravaniAK

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

• ~~OWNERS~~ [Cali0707]

Approvers can indicate their approval by writing /approve in a comment Approvers can cancel approval by writing /approve cancel in a comment