remove eagle converter and reference (#672)

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<!-- PLEASE FILL IN THE PR DESCRIPTION HERE ENSURING ALL CHECKLIST ITEMS
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## Purpose
Deprecate old eagle converter pathway. It's incompatible with rest of
our converters and we haven't seen enough community engagement.

## Tests

## Checklist

I have filled in:

- [x] The purpose of the PR, such as "Fix some issue (link existing
issues this PR will resolve)".
- [x] The test plan/results, such as providing test command and pasting
the results.
- [ ] (Optional) The necessary documentation update.
- [x] I (a human) have written or reviewed the code in this pr to the
best of my ability.

Signed-off-by: shanjiaz <hezhao@redhat.com>
Co-authored-by: shanjiaz <hezhao@redhat.com>

Author: shanjiaz

src/speculators/convert/eagle/__init__.py

@@ -3,6 +3,5 @@
 """
 
 from speculators.convert.eagle.eagle3_converter import Eagle3Converter
-from speculators.convert.eagle.eagle_converter import EagleConverter
 
-__all__ = ["Eagle3Converter", "EagleConverter"]
+__all__ = ["Eagle3Converter"]