Bump GoSAML dependency (#20092)

```release-note
NONE
```

go.mod

@@ -38,7 +38,7 @@ require (
 	github.com/ledongthuc/pdf v0.0.0-20220302134840-0c2507a12d80
 	github.com/lib/pq v1.10.4
 	github.com/mattermost/go-i18n v1.11.1-0.20211013152124-5c415071e404
-	github.com/mattermost/gosaml2 v0.8.0
+	github.com/mattermost/gosaml2 v0.8.1-0.20220428161029-8c99721fdec4
 	github.com/mattermost/gziphandler v0.0.1
 	github.com/mattermost/ldap v0.0.0-20201202150706-ee0e6284187d
 	github.com/mattermost/logr/v2 v2.0.15

go.sum

@@ -921,8 +921,8 @@ github.com/markbates/safe v1.0.1/go.mod h1:nAqgmRi7cY2nqMc92/bSEeQA+R4OheNU2T1kN
 github.com/marstr/guid v1.1.0/go.mod h1:74gB1z2wpxxInTG6yaqA7KrtM0NZ+RbrcqDvYHefzho=
 github.com/mattermost/go-i18n v1.11.1-0.20211013152124-5c415071e404 h1:Khvh6waxG1cHc4Cz5ef9n3XVCxRWpAKUtqg9PJl5+y8=
 github.com/mattermost/go-i18n v1.11.1-0.20211013152124-5c415071e404/go.mod h1:RyS7FDNQlzF1PsjbJWHRI35exqaKGSO9qD4iv8QjE34=
-github.com/mattermost/gosaml2 v0.8.0 h1:nkYiByawqwJ7KncK1LDWKwTx5aRarBTQsmH+XcCVsWQ=
-github.com/mattermost/gosaml2 v0.8.0/go.mod h1:1nMAdE2Psxaz+pj79Oytayi+hC3aZUi3SmJQlIe+sLM=
+github.com/mattermost/gosaml2 v0.8.1-0.20220428161029-8c99721fdec4 h1:y102PXr0vul3Dcw1xP4fs6R3lFL2kyLsC3qI6lsgCVQ=
+github.com/mattermost/gosaml2 v0.8.1-0.20220428161029-8c99721fdec4/go.mod h1:1nMAdE2Psxaz+pj79Oytayi+hC3aZUi3SmJQlIe+sLM=
 github.com/mattermost/gziphandler v0.0.1 h1:uXHcXF5agnQ6bXabvpiwwwZOlCYoa7mKHH0lxns/o8w=
 github.com/mattermost/gziphandler v0.0.1/go.mod h1:CvvZR7sXqhj81V2swXuQY7T04Ccc89u7W7pHNPKev8g=
 github.com/mattermost/ldap v0.0.0-20201202150706-ee0e6284187d h1:/RJ/UV7M5c7L2TQ0KNm4yZxxFvC1nvRz/gY/Daa35aI=

vendor/github.com/mattermost/gosaml2/types/encrypted_key.go

@@ -18,6 +18,7 @@ import (
 	"bytes"
 	"crypto/aes"
 	"crypto/cipher"
+	"crypto/des"
 	"crypto/rand"
 	"crypto/rsa"
 	"crypto/sha1"
@@ -173,11 +174,17 @@ func (ek *EncryptedKey) DecryptSymmetricKey(cert *tls.Certificate) (cipher.Block
 			//The RSA v1.5 Key Transport algorithm given below are those used in conjunction with TRIPLEDES
 			//Please also see https://www.w3.org/TR/xmlenc-core/#sec-Algorithms and
 			//https://www.w3.org/TR/xmlenc-core/#rsav15note.
-			b, err := aes.NewCipher(pt)
+			b, err := des.NewTripleDESCipher(pt)
 			if err != nil {
 				return nil, err
 			}
 
+			// FIXME: The version we had previously in our fork, AES seems more secure from my Googling.
+			// b, err := aes.NewCipher(pt)
+			// if err != nil {
+			// 	return nil, err
+			// }
+
 			return b, nil
 		default:
 			return nil, fmt.Errorf("unsupported encryption algorithm: %s", ek.EncryptionMethod.Algorithm)

vendor/modules.txt

@@ -433,7 +433,7 @@ github.com/mattermost/go-i18n/i18n
 github.com/mattermost/go-i18n/i18n/bundle
 github.com/mattermost/go-i18n/i18n/language
 github.com/mattermost/go-i18n/i18n/translation
-# github.com/mattermost/gosaml2 v0.8.0
+# github.com/mattermost/gosaml2 v0.8.1-0.20220428161029-8c99721fdec4
 ## explicit; go 1.13
 github.com/mattermost/gosaml2
 github.com/mattermost/gosaml2/types