fix(deps): update module golang.org/x/mod to v0.21.0 (#1397)

This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| golang.org/x/mod | `v0.20.0` -> `v0.21.0` |
[![age](https://developer.mend.io/api/mc/badges/age/go/golang.org%2fx%2fmod/v0.21.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![adoption](https://developer.mend.io/api/mc/badges/adoption/go/golang.org%2fx%2fmod/v0.21.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![passing](https://developer.mend.io/api/mc/badges/compatibility/go/golang.org%2fx%2fmod/v0.20.0/v0.21.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/go/golang.org%2fx%2fmod/v0.20.0/v0.21.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|

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core/go.mod

@@ -1,8 +1,8 @@
 module github.com/open-feature/flagd/core
 
-go 1.21
+go 1.22.0
 
-toolchain go1.22.6
+toolchain go1.22.7
 
 require (
 	buf.build/gen/go/open-feature/flagd/grpc/go v1.5.1-20240215170432-1e611e2999cc.1
@@ -34,7 +34,7 @@ require (
 	gocloud.dev v0.37.0
 	golang.org/x/crypto v0.27.0
 	golang.org/x/exp v0.0.0-20240506185415-9bf2ced13842
-	golang.org/x/mod v0.20.0
+	golang.org/x/mod v0.21.0
 	golang.org/x/sync v0.8.0
 	google.golang.org/grpc v1.66.0
 	gopkg.in/yaml.v3 v3.0.1

core/go.sum

@@ -1786,6 +1786,8 @@ golang.org/x/mod v0.19.0 h1:fEdghXQSo20giMthA7cd28ZC+jts4amQ3YMXiP5oMQ8=
 golang.org/x/mod v0.19.0/go.mod h1:hTbmBsO62+eylJbnUtE2MGJUyE7QWk4xUqPFrRgJ+7c=
 golang.org/x/mod v0.20.0 h1:utOm6MM3R3dnawAiJgn0y+xvuYRsm1RKM/4giyfDgV0=
 golang.org/x/mod v0.20.0/go.mod h1:hTbmBsO62+eylJbnUtE2MGJUyE7QWk4xUqPFrRgJ+7c=
+golang.org/x/mod v0.21.0 h1:vvrHzRwRfVKSiLrG+d4FMl/Qi4ukBCE6kZlTUkDYRT0=
+golang.org/x/mod v0.21.0/go.mod h1:6SkKJ3Xj0I0BrPOZoBy3bdMptDDU9oJrpohJ3eWZ1fY=
 golang.org/x/net v0.0.0-20180724234803-3673e40ba225/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
 golang.org/x/net v0.0.0-20180826012351-8a410e7b638d/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=
 golang.org/x/net v0.0.0-20190108225652-1e06a53dbb7e/go.mod h1:mL1N/T3taQHkDXs73rZJwtUhF3w3ftmwwsq0BUmARs4=