Use cbor2's fuzzing harness (google#14749)

I moved cbor2's fuzzing harness into the project repo:
agronholm/cbor2#234

So now OSS-Fuzz can use that instead of this local copy 👍

Author: mschwager

projects/cbor2/Dockerfile

@@ -1,4 +1,4 @@
-# Copyright 2024 Google LLC
+# Copyright 2026 Google LLC
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -17,4 +17,4 @@
 FROM gcr.io/oss-fuzz-base/base-builder-python
 RUN git clone --depth 1 https://github.com/agronholm/cbor2.git
 WORKDIR cbor2
-COPY build.sh *.py $SRC/
+COPY build.sh $SRC/