vendor: update buildkit to v0.28.0-rc1

Signed-off-by: Tonis Tiigi <tonistiigi@gmail.com>

vendor/github.com/aws/aws-sdk-go-v2/config/shared_config.go

@@ -125,6 +125,8 @@ const (
 	checksumWhenRequired          = "when_required"
 
 	authSchemePreferenceKey = "auth_scheme_preference"
+
+	loginSessionKey = "login_session"
 )
 
 // defaultSharedConfigProfile allows for swapping the default profile for testing
@@ -362,6 +364,9 @@ type SharedConfig struct {
 
 	// Priority list of preferred auth scheme names (e.g. sigv4a).
 	AuthSchemePreference []string
+
+	// Session ARN from an `aws login` session.
+	LoginSession string
 }
 
 func (c SharedConfig) getDefaultsMode(ctx context.Context) (value aws.DefaultsMode, ok bool, err error) {
@@ -897,6 +902,8 @@ func mergeSections(dst *ini.Sections, src ini.Sections) error {
 			ssoStartURLKey,
 
 			authSchemePreferenceKey,
+
+			loginSessionKey,
 		}
 		for i := range stringKeys {
 			if err := mergeStringKey(&srcSection, &dstSection, sectionName, stringKeys[i]); err != nil {
@@ -1175,6 +1182,8 @@ func (c *SharedConfig) setFromIniSection(profile string, section ini.Section) er
 
 	c.AuthSchemePreference = toAuthSchemePreferenceList(section.String(authSchemePreferenceKey))
 
+	updateString(&c.LoginSession, section, loginSessionKey)
+
 	return nil
 }