Update DefaultDevfileRegistry link in IBM-Z and Power doc

[xkwangcn]

What type of PR is this?

Uncomment only one /kind line, and delete the rest.
For example, > /kind bug would simply become: /kind bug

/kind bug
/kind feature
/kind cleanup
/kind tests
/kind documentation
Feel free to use other labels as needed. However one of the above labels must be present or the PR will not be reviewed. This instruction is for reviewers as well.

What does this PR do / why we need it:

In doc: https://odo.dev/docs/tutorials/deploying-a-devfile-using-odo-on-ibm-z-and-power/#deploying-your-first-devfile-on-ibm-z--power, DefaultDevfileRegistry use old link https://github.com/odo-devfiles/registry, need update it to https://registry.devfile.io/viewer
Which issue(s) this PR fixes:

Fixes #?

PR acceptance criteria:

• Unit test

• Integration test

• Documentation

• I have read the test guidelines

How to test changes / Special notes to the reviewer:

[netlify]

✔️ Deploy Preview for odo-docusaurus-preview ready!

🔨 Explore the source changes: 13d2ae2

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[sonarcloud]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

No Coverage information
No Duplication information

[xkwangcn]

/area system-PZ

[openshift-ci]

Hi @xkwangcn. Thanks for your PR.

I'm waiting for a openshift member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

I understand the commands that are listed here.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.

[dharmit]

/approve
/lgtm

[openshift-ci]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: dharmit

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