dependabot: put rust-vmm deps into separate PR

rust-vmm deps have to be updated in lockstep most of the time, due to
tight inter-dependencies. However, releasing new versions of all
rust-vmm crates often takes time, and having dependabot include partial
rust-vmm updates in its big PR of the week just results in broken
dependabot PRs. Thus, just sort out the rust-vmm dependencies into a
separate PR (dependabot opens one PR per "group", and each dependency
update is only included in the first group that matches it).

Signed-off-by: Patrick Roy <[email protected]>

Author: roypat

.github/dependabot.yml

@@ -9,6 +9,17 @@ updates:
       - dependency-type: "all"
     open-pull-requests-limit: 100
     groups:
+      rust-vmm:
+        patterns:
+          - "vmm-sys-util"
+          - "kvm-bindings"
+          - "kvm-ioctls"
+          - "vm-memory"
+          - "vhost"
+          - "linux-loader"
+          - "vm-allocator"
+          - "event-manager"
+          - "vm-superio"
       firecracker:
         patterns:
           - "*"