Release Version 0.5.2

[toddbaert]

Release checklist:

• [x] Release spec v0.5.2
• [x] Update spec badge on the org readme
• [x] Create PRs in the SDK repos containing the new requirements
  • https://github.com/open-feature/dotnet-sdk/pull/101
  • https://github.com/open-feature/java-sdk/pull/240
  • https://github.com/open-feature/js-sdk/pull/360
  • https://github.com/open-feature/go-sdk/pull/136
• [x] Update docs https://github.com/open-feature/docs.openfeature.dev/pull/247

Spec v0.5.2 badge