fix(deps): update module github.com/open-feature/flagd/core to v0.9.0 (#1281)

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This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
|
[github.com/open-feature/flagd/core](https://togithub.com/open-feature/flagd)
| `v0.8.2` -> `v0.9.0` |
[![age](https://developer.mend.io/api/mc/badges/age/go/github.com%2fopen-feature%2fflagd%2fcore/v0.9.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![adoption](https://developer.mend.io/api/mc/badges/adoption/go/github.com%2fopen-feature%2fflagd%2fcore/v0.9.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![passing](https://developer.mend.io/api/mc/badges/compatibility/go/github.com%2fopen-feature%2fflagd%2fcore/v0.8.2/v0.9.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
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flagd-proxy/go.mod

@@ -9,7 +9,7 @@ require (
 	buf.build/gen/go/open-feature/flagd/protocolbuffers/go v1.33.0-20240215170432-1e611e2999cc.1
 	github.com/dimiro1/banner v1.1.0
 	github.com/mattn/go-colorable v0.1.13
-	github.com/open-feature/flagd/core v0.8.2
+	github.com/open-feature/flagd/core v0.9.0
 	github.com/prometheus/client_golang v1.19.0
 	github.com/spf13/cobra v1.8.0
 	github.com/spf13/viper v1.18.2

flagd/go.mod

@@ -12,7 +12,7 @@ require (
 	github.com/dimiro1/banner v1.1.0
 	github.com/gorilla/mux v1.8.1
 	github.com/mattn/go-colorable v0.1.13
-	github.com/open-feature/flagd/core v0.8.2
+	github.com/open-feature/flagd/core v0.9.0
 	github.com/prometheus/client_golang v1.19.0
 	github.com/rs/cors v1.10.1
 	github.com/rs/xid v1.5.0