Bump powsybl-core to 6.4.1

[flo-dup]

Please check if the PR fulfills these requirements

• [x] The commit message follows our guidelines

What kind of change does this PR introduce? Dependency update

What is the current behavior? powsybl-core 6.4.0

What is the new behavior (if this is a feature change)? powsybl-core 6.4.1

Does this PR introduce a breaking change or deprecate an API?

• [ ] Yes
• [x] No

Other information: powsybl-core 6.4.0 should not be used as it brought inconsistencies which are fixed in powsybl-core 6.4.1

[sonarcloud[bot]]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud