revert sccache builds, as GHA does not like it

Dockerfile

@@ -4,17 +4,10 @@ RUN apt install -y libssl-dev mold
 WORKDIR /app
 COPY . /app
 ENV CARGO_REGISTRIES_CRATES_IO_PROTOCOL=sparse
-RUN wget https://github.com/mozilla/sccache/releases/download/v0.2.15/sccache-v0.2.15-x86_64-unknown-linux-musl.tar.gz \
-    && tar xzf sccache-v0.2.15-x86_64-unknown-linux-musl.tar.gz \
-    && mv sccache-v0.2.15-x86_64-unknown-linux-musl/sccache /usr/local/bin/sccache \
-    && chmod +x /usr/local/bin/sccache
-ENV RUSTC_WRAPPER=/usr/local/bin/sccache
-ENV SCCACHE_DIR=/root/.cache/sccache
 ENV RUSTFLAGS="-C link-arg=-B/usr/bin/mold"
 # copy build artifact somewhere accessible so we can copy it in the next stage
 RUN --mount=type=cache,target=/root/.cargo \
- --mount=type=cache,target=/root/.cache/sccache \
- cargo build --release
+    cargo build --release
 
 FROM redhat/ubi9-micro:latest
 # RUN useradd -u 1001 chisel