fix: correcting title of attestations[].map[].counterClaim (#374)

Fixes #373 which addresses a small typo in the `counterClaim` field
title in the Attestation 1.6

schema/bom-1.6.schema.json

@@ -178,7 +178,7 @@
                     },
                     "counterClaims": {
                       "type": "array",
-                      "title": "Claims",
+                      "title": "Counter Claims",
                       "description": "The list of  `bom-ref` to the counter claims being attested to.",
                       "items": { "$ref": "#/definitions/refLinkType" }
                     },