[classifier] simplify regexes

There is not much we can do with regexes in YAML file to make them
more readable, but simplify them a bit more.

classifier.yaml

@@ -20,30 +20,30 @@ matchers:
       member: "\\1"
       pod: "\\2"
   # Groups
-  - "^to([12])-p(\\d+)\\.":
+  - "^to[12]-p\\d+\\.":
       groups:
         - tor
         - tor-bgp
         - tor-bgp-compute
-  - "^to([12])-ap(\\d+)\\.":
+  - "^to[12]-ap\\d+\\.":
       groups:
         - tor
         - tor-bgp
         - tor-bgp-admin
-  - "^to([12])-sp(\\d+)\\.":
+  - "^to[12]-sp\\d+\\.":
       groups:
         - tor
         - tor-bgp
         - tor-bgp-storage
-  - "^spine(\\d+)\\.":
+  - "^spine\\d+\\.":
       groups:
         - spine
         - spine-bgp
-  - "^s-spine(\\d+)\\.":
+  - "^s-spine\\d+\\.":
       groups:
         - sspine
         - sspine-bgp
-  - "^con(\\d+)-n(\\d+)\\.":
+  - "^con\\d+-n\\d+\\.":
       groups:
         - console
   - "^edge\\d+\\.":
@@ -52,47 +52,47 @@ matchers:
   - "^ob[1-4]-":
       groups:
         - oob
-  - "^gateway[12]\\.(sk1|ussfo03)\\.":
+  - "^gateway[12]\\.":
       os: linux
       groups:
         - adm-gateway
   # Vendor
-  - "^to([12])-(p|ap)(\\d+)\\.(sk1)\\.":
+  - "^to[12]-(p|ap)\\d+\\.sk1\\.":
       os: cumulus
       model: dell-s4048
-  - "^to([12])-sp(\\d+)\\.(sk1)\\.":
+  - "^to[12]-sp\\d+\\.sk1\\.":
       os: cumulus
       model: dell-s6010
-  - "^to([12])-(p|ap|sp)(\\d+)\\.(ussfo03)\\.":
+  - "^to[12]-(p|ap|sp)\\d+\\.ussfo03\\.":
       os: cumulus
       model: wedge100
-  - "^to([12])-p2\\.(ussfo03)\\.":
+  - "^to[12]-p2\\.ussfo03\\.":
       os: junos
       model: qfx5110-48s
-  - "^spine(\\d+)\\.(sk1)\\.":
+  - "^spine\\d+\\.sk1\\.":
       os: cumulus
       model: dell-s6010
-  - "^spine(\\d+)\\.(ussfo03)\\.":
+  - "^spine\\d+\\.ussfo03\\.":
       os: cumulus
       model: wedge100
-  - "^con(\\d+)-n(\\d+)\\.(sk1)\\.":
+  - "^con\\d+-n\\d+\\.sk1\\.":
       os: opengear
       model: cm7116-2-sac
-  - "^con(\\d+)-n(\\d+)\\.(ussfo03)\\.":
+  - "^con\\d+-n\\d+\\.ussfo03\\.":
       os: opengear
       model: cm7116-2-dac
-  - "^con(\\d+)-ag(\\d+)\\.(ussfo03)\\.":
+  - "^con\\d+-ag\\d+\\.ussfo03\\.":
       os: opengear
       model: cm7132-2-dac
-  - "^s-spine[12]\\.(ussfo03)\\.":
+  - "^s-spine[12]\\.ussfo03\\.":
       os: cumulus
       model: wedge100
-  - "^edge\\d+\\.(ussfo03)\\.":
+  - "^edge\\d+\\.ussfo03\\.":
       os: junos
       model: qfx10002-36q
-  - "^edge\\d+\\.(sk1)\\.":
+  - "^edge\\d+\\.sk1\\.":
       os: iosxr
       model: asr9k
-  - "^ob[1-4]-([s]?p|ag|n)\\d+\\.":
+  - "^ob[1-4]-(p|sp|ag|n)\\d+\\.":
       os: ios
       model: c2960s