chore: simplify build to fixed Tencent pip mirror

Dockerfile

@@ -7,40 +7,11 @@ ENV PYTHONDONTWRITEBYTECODE=1 \
 
 ARG PIP_INDEX_URL=https://mirrors.cloud.tencent.com/pypi/simple
 ARG PIP_TRUSTED_HOST=mirrors.cloud.tencent.com
-ARG PIP_REGION=auto
 
 COPY requirements.txt /app/requirements.txt
-RUN set -e; \
-    region="${PIP_REGION}"; \
-    if [ "${region}" = "auto" ]; then \
-      region=$(python - <<'PY'
-import urllib.request
-urls = [
-    "https://ipapi.co/country/",
-    "https://ifconfig.co/country-iso",
-]
-for u in urls:
-    try:
-        with urllib.request.urlopen(u, timeout=3) as r:
-            v = r.read().decode("utf-8", errors="ignore").strip().upper()
-            if v:
-                print(v)
-                raise SystemExit(0)
-    except Exception:
-        pass
-print("UNKNOWN")
-PY
-); \
-    fi; \
-    echo "[build] PIP region=${region}"; \
-    if [ "${region}" = "CN" ]; then \
-      pip install --no-cache-dir --retries 5 --timeout 120 \
-        -i "${PIP_INDEX_URL}" --trusted-host "${PIP_TRUSTED_HOST}" \
-        -r /app/requirements.txt \
-      || pip install --no-cache-dir --retries 5 --timeout 120 -r /app/requirements.txt; \
-    else \
-      pip install --no-cache-dir --retries 5 --timeout 120 -r /app/requirements.txt; \
-    fi
+RUN pip install --no-cache-dir --retries 5 --timeout 120 \
+    -i "${PIP_INDEX_URL}" --trusted-host "${PIP_TRUSTED_HOST}" \
+    -r /app/requirements.txt
 
 COPY app /app/app