Upper bounds for dns-stub

Error:
```
File "mirage/stub/dns_stub_mirage.ml", line 61, characters 13-48:
61 |   module H = Happy_eyeballs_mirage.Make(T)(C)(S)
                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Error: The functor application is ill-typed.
       These arguments:
         T C S
       do not match these parameters:
         functor (S : Tcpip.Stack.V4V6) -> ...
       1. The following extra argument is provided
              T : sig val sleep_ns : int64 -> unit Lwt.t end
       2. The following extra argument is provided
              C :
              sig
                val elapsed_ns : unit -> int64
                val period_ns : unit -> int64 option
              end
       3. Module S matches the expected module type Tcpip.Stack.V4V6
```

Author: hannesm

packages/dns-stub/dns-stub.8.0.0/opam

@@ -25,6 +25,7 @@ depends: [
   "mirage-random" {>= "2.0.0"}
   "tcpip" {>= "7.0.0"}
   "metrics"
+  "happy-eyeballs-mirage" {< "2.0.0"}
 ]
 
 build: [

packages/dns-stub/dns-stub.9.0.0/opam

@@ -25,6 +25,7 @@ depends: [
   "tcpip" {>= "8.2.0"}
   "metrics"
   "mirage-crypto-rng-mirage" {>= "1.0.0"}
+  "happy-eyeballs-mirage" {< "2.0.0"}
 ]
 
 build: [

packages/dns-stub/dns-stub.9.1.0/opam

@@ -25,6 +25,7 @@ depends: [
   "tcpip" {>= "8.2.0"}
   "metrics"
   "mirage-crypto-rng-mirage" {>= "1.0.0"}
+  "happy-eyeballs-mirage" {< "2.0.0"}
 ]
 
 build: [