kvm: Update Debian versions

As Debian Bullseye has been released, set it as first option.

As Debian Buster 10.11 update has been released, upgrade it.

software/kvm/instance-kvm-cluster-input-schema.json

@@ -474,9 +474,15 @@
               "oneOf": [
                 {
                   "const": [
-                    "https://shacache.nxdcdn.com/0a6aee1d9aafc1ed095105c052f9fdd65ed00ea9274188c9cd0072c8e6838ab40e246d45a1e6956d74ef1b04a1fc042151762f25412e9ff0cbf49418eef7992e#a3ebc76aec372808ad80000108a2593a"
+                    "https://shacache.nxdcdn.com/02257c3ec27e45d9f022c181a69b59da67e5c72871cdb4f9a69db323a1fad58093f2e69702d29aa98f5f65e920e0b970d816475a5a936e1f3bf33832257b7e92#b710c178eb434d79ce40ce703d30a5f0"
                   ],
-                  "title": "Debian Buster 10.5 netinst x86_64"
+                  "title": "Debian Bullseye 11.1 netinst x86_64"
+                },
+                {
+                  "const": [
+                    "https://shacache.nxdcdn.com/d82b0510fd919c2a851ee93ea0f7ad6779bfa597297a5c7463b63746799f001321ec4c9b8ba6cfe20248dd2da28100ad3b78e74489a8c0c573238f226a509a9d#9d7b9cc850464d60ac174787c53e8f3f"
+                  ],
+                  "title": "Debian Buster 10.11 netinst x86_64"
                 },
                 {
                   "const": [