rebase: bump github.com/aws/aws-sdk-go-v2/service/sts

Bumps [github.com/aws/aws-sdk-go-v2/service/sts](https://github.com/aws/aws-sdk-go-v2) from 1.21.2 to 1.21.5.
- [Release notes](https://github.com/aws/aws-sdk-go-v2/releases)
- [Commits](https://github.com/aws/aws-sdk-go-v2/compare/service/efs/v1.21.2...service/efs/v1.21.5)

---
updated-dependencies:
- dependency-name: github.com/aws/aws-sdk-go-v2/service/sts
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

vendor/github.com/aws/aws-sdk-go-v2/aws/go_module_metadata.go

@@ -3,4 +3,4 @@
 package aws
 
 // goModuleVersion is the tagged release for this module
-const goModuleVersion = "1.20.1"
+const goModuleVersion = "1.21.0"

vendor/github.com/aws/aws-sdk-go-v2/aws/protocol/query/object.go

@@ -41,6 +41,12 @@ func (o *Object) Key(name string) Value {
 	return o.key(name, false)
 }
 
+// KeyWithValues adds the given named key to the Query object.
+// Returns a Value encoder that should be used to encode a Query list of values.
+func (o *Object) KeyWithValues(name string) Value {
+	return o.keyWithValues(name, false)
+}
+
 // FlatKey adds the given named key to the Query object.
 // Returns a Value encoder that should be used to encode a Query value type. The
 // value will be flattened if it is a map or array.
@@ -54,3 +60,10 @@ func (o *Object) key(name string, flatValue bool) Value {
 	}
 	return newValue(o.values, name, flatValue)
 }
+
+func (o *Object) keyWithValues(name string, flatValue bool) Value {
+	if o.prefix != "" {
+		return newAppendValue(o.values, fmt.Sprintf("%s.%s", o.prefix, name), flatValue)
+	}
+	return newAppendValue(o.values, name, flatValue)
+}

vendor/github.com/aws/aws-sdk-go-v2/aws/protocol/query/value.go

@@ -27,6 +27,15 @@ func newValue(values url.Values, key string, flat bool) Value {
 	}
 }
 
+func newAppendValue(values url.Values, key string, flat bool) Value {
+	return Value{
+		values:     values,
+		key:        key,
+		flat:       flat,
+		queryValue: httpbinding.NewQueryValue(values, key, true),
+	}
+}
+
 func newBaseValue(values url.Values) Value {
 	return Value{
 		values:     values,

vendor/github.com/aws/aws-sdk-go-v2/aws/signer/internal/v4/headers.go

@@ -48,6 +48,7 @@ var RequiredSignedHeaders = Rules{
 			"X-Amz-Request-Payer":                                         struct{}{},
 			"X-Amz-Server-Side-Encryption":                                struct{}{},
 			"X-Amz-Server-Side-Encryption-Aws-Kms-Key-Id":                 struct{}{},
+			"X-Amz-Server-Side-Encryption-Context":                        struct{}{},
 			"X-Amz-Server-Side-Encryption-Customer-Algorithm":             struct{}{},
 			"X-Amz-Server-Side-Encryption-Customer-Key":                   struct{}{},
 			"X-Amz-Server-Side-Encryption-Customer-Key-Md5":               struct{}{},