allow rolling upgrades, remove same MinIO version requirement (#9033)

Upgrades between releases are failing due to strict
rule to avoid rolling upgrades, it is enough to
bump up APIs between versions to allow for quorum
failure and wait times. Authentication failures are
catastrophic in nature which leads to server not
be able to upgrade properly.

Fixes #9021
Fixes #8968

cmd/jwt.go

@@ -86,7 +86,6 @@ func authenticateNode(accessKey, secretKey, audience string) (string, error) {
 	claims.SetExpiry(UTCNow().Add(defaultInterNodeJWTExpiry))
 	claims.SetAccessKey(accessKey)
 	claims.SetAudience(audience)
-	claims.SetIssuer(ReleaseTag)
 
 	jwt := jwtgo.NewWithClaims(jwtgo.SigningMethodHS512, claims)
 	return jwt.SignedString([]byte(secretKey))

cmd/storage-rest-server.go

@@ -79,10 +79,6 @@ func storageServerRequestValidate(r *http.Request) error {
 		return errAuthentication
 	}
 
-	if claims.Issuer != ReleaseTag {
-		return errAuthentication
-	}
-
 	requestTimeStr := r.Header.Get("X-Minio-Time")
 	requestTime, err := time.Parse(time.RFC3339, requestTimeStr)
 	if err != nil {