Update error message when executing kedro run without pipeline

[ravi-kumar-pilla]

Description

Resolves #3794

Development notes

• Add warning message for kedro new doc
• Add warning message when user selects no example pipeline when running kedro new without --starter
• Improve error message when user executes kedro run on an empty kedro project

Developer Certificate of Origin

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Checklist

• Read the contributing guidelines
• Signed off each commit with a Developer Certificate of Origin (DCO)
• Opened this PR as a 'Draft Pull Request' if it is work-in-progress
• Updated the documentation to reflect the code changes
• Added a description of this change in the RELEASE.md file
• Added tests to cover my changes
• Checked if this change will affect Kedro-Viz, and if so, communicated that with the Viz team