Update node version for integration tests

[cffls]

This commit made a few changes:

1. Upgrade cardano-node version to v8.x.x from v1.x.x. This will help with testing when entering Chang hardfork.
2. Upgrade ogmios to 6.x.x because of change 1.
3. Replace built-in ogmios chain context with https://gitlab.com/viperscience/ogmios-python because of change 2.
4. Temporarily disable Kupo in integration test because ogmios-python doesn't support kupo yet.

[codecov]

Codecov Report

Attention: Patch coverage is 66.66667% with 1 lines in your changes are missing coverage. Please review.

Project coverage is 83.61%. Comparing base (486d97f) to head (386191a).

Files	Patch %	Lines
pycardano/backend/cardano_cli.py	66.66%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #345      +/-   ##
==========================================
- Coverage   83.62%   83.61%   -0.02%     
==========================================
  Files          29       29              
  Lines        3719     3722       +3     
  Branches      936      939       +3     
==========================================
+ Hits         3110     3112       +2     
  Misses        445      445              
- Partials      164      165       +1     

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[nielstron]

LGTM