docs: add AM 4.0 changes

[passionne]

This PR update the documentation with AM 4.0 changes:

• fix(am): update AM version to 4.0.0
• fix(am): addition of migration note for 3.21 about MongoDB indexes
• docs: mention enterprise edition plugin in breaking changes

  🚀 CI was able to deploy the build of this PR, so you can now try it directly here

[sonarcloud[bot]]

Kudos, SonarCloud Quality Gate passed!   

0 Bugs
0 Vulnerabilities
0 Security Hotspots
0 Code Smells

No Coverage information
0.0% Duplication