Add ff semconv to sigs.yml

sigs.yml

@@ -219,6 +219,24 @@
     gcLiaison:
       - name: 'Daniel Gomez Blanco'
         github: danielgblanco
+  - name: 'Semantic Conventions: Sustainability'
+    meeting: Every Second Monday at 7:30 PT
+    notes:
+      type: gDoc
+      value: 1x9hprUaUNlVCZMtFAqBcj6h50ukpT0hCAli7BzgWsTQ
+    chat:
+      - type: slack
+        name: '#otel-ff-semconv'
+        id: C07AES1JN56
+    invites: calendar-semconv
+    sponsors:
+      - name: Daniel Dyla
+        github: dyladan
+      - name: Alexander Wert
+        github: AlexanderWert
+    gcLiaison:
+      - name: Daniel Dyla
+        github: dyladan
   - name: 'Specification: Entities'
     meeting: Every other week on Thursday at 08:00 AM PT
     notes: