Remove the example and link to the Principles for Digital Development

[Lucyeoh]

Update:

Now we have a wiki and more sophisticated helper text I don't think we should put examples in the Standard itself.

Suggest we include this in a list of examples of best practices in the helper text, not in the core standard.

I propose this to be a minor change - happy to discuss in council though

Fixes # .

Changes proposed in this pull request:

Propagation of Changes

Identify where of the following the proposed changes need to be propagated, and include the relevant pull request where appropriate:

• The DPGA website contains https://digitalpublicgoods.net/standard/ which needs to be updated manually matching the contents of standard.md.
• The DPGA website also contains the submission guide which needs to be updated manually.
• The DPG application webapp admin panel which will be updated manually.
• The Eligibility Form through the unicef/publicgoods-scripts repository, by editing quizQuestions.js