chore(deps): update bitnami/oras docker tag to v1.2.1 (#507)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| bitnami/oras | final | patch | `1.2.0` -> `1.2.1` |

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dockerfiles/ci/base/Dockerfile

@@ -93,7 +93,7 @@ RUN folder=$([ "$(arch)" = "x86_64" ] && echo linux || echo aarch64); \
 
 # oras tool
 # renovate: datasource=github-tags depName=oras-project/oras
-COPY --from=bitnami/oras:1.2.0 /oras /usr/local/bin/oras
+COPY --from=bitnami/oras:1.2.1 /oras /usr/local/bin/oras
 
 # gh-ost
 # linux amd64 only