Remove ERV analysis script (#528)

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# PR Details
## Description
The ERV analysis script is not part of the K900 release and should be
removed from the release candidate branch. The script is already moved
into a dedicated repos
https://github.com/usdot-fhwa-stol/carma-analytics-fotda that has all
the past analysis script for different use cases
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## Related Issue
NA
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## Motivation and Context

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## How Has This Been Tested?
NA
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## Types of changes

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- [x] Defect fix (non-breaking change that fixes an issue)
- [ ] New feature (non-breaking change that adds functionality)
- [ ] Breaking change (fix or feature that cause existing functionality
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## Checklist:

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- [ ] I have added any new packages to the sonar-scanner.properties file
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- [ ] I have updated the documentation accordingly.
- [x] I have read the **CONTRIBUTING** document.
[V2XHUB Contributing
Guide](https://github.com/usdot-fhwa-OPS/V2X-Hub/blob/develop/Contributing.md)
- [ ] I have added tests to cover my changes.
- [ ] All new and existing tests passed.