dockerimg: remove buildx dependencies from Dockerfile

Main changes:
1. Removed --mount=type=cache for apt-get operations and added cleanup steps
2. Removed --mount=type=cache for Go tools installation

Co-Authored-By: sketch <hello@sketch.dev>
diff --git a/dockerimg/testdata/testcreatedockerfile_empty_repo.dockerfile b/dockerimg/testdata/testcreatedockerfile_empty_repo.dockerfile
index 0ae81e9..cc73fbd 100644
--- a/dockerimg/testdata/testcreatedockerfile_empty_repo.dockerfile
+++ b/dockerimg/testdata/testcreatedockerfile_empty_repo.dockerfile
@@ -1,4 +1,4 @@
-FROM ghcr.io/boldsoftware/sketch:86ef7a672f85139e73f38d4cdf78d95f
+FROM ghcr.io/boldsoftware/sketch:3a03b430af3cabf3415d263b7803b311
 
 ARG GIT_USER_EMAIL
 ARG GIT_USER_NAME
@@ -6,23 +6,16 @@
 RUN git config --global user.email "$GIT_USER_EMAIL" && \
     git config --global user.name "$GIT_USER_NAME"
 
-LABEL sketch_context="5820b50cae54d2fbdd28081f960dcfac4367f8d805030ecd612a13ebeef13bb1"
+LABEL sketch_context="6f16c9b83fbd20e2eb242922989364954adb4905ab8c562baf2bc906ee347da5"
 COPY . /app
 
 WORKDIR /app
 RUN if [ -f go.mod ]; then go mod download; fi
 
-RUN --mount=type=cache,target=/var/cache/apt \
-    set -eux; \
-    apt-get update && \
-    apt-get install -y --no-install-recommends python3-pip python3-venv || true
+# Install any Python dependencies but continue if setup fails
+RUN if [ -f requirements.txt ]; then pip3 install -r requirements.txt || true; fi
 
-# Set up Python environment, allowing failures to not stop the build
-RUN python3 -m pip install --upgrade pip || true
-
-# Install any Go tools specific to this project if needed
-RUN --mount=type=cache,target=/go/pkg/mod \
-    --mount=type=cache,target=/root/.cache/go-build \
-    go install github.com/golangci/golangci-lint/cmd/golangci-lint@latest || true
+# Ensure Go development tools are properly set up
+RUN go mod tidy || true
 
 CMD ["/bin/sketch"]