Rename Linux release script to release_linux.sh and align with macOS

Rename build_release_linux.sh to release_linux.sh.
Align its structure and capabilities with release_macos.sh, adding support for dry runs, robust temp directory cleanup, and customizable CIBWHEEL_BIN.

PiperOrigin-RevId: 922429425

Author: dmitriplotnikov

release/kokoro/release_linux.cfg

@@ -0,0 +1,5 @@
+# proto-file: //devtools/kokoro/config/proto/build.proto
+# proto-message: BuildConfig
+
+build_file: "cel-python/release/kokoro/release_linux.sh"
+timeout_mins: 120

release/kokoro/release_linux.sh

@@ -0,0 +1,76 @@
+#!/bin/bash
+set -e
+
+# If running locally (not on Kokoro), authenticate with gcloud.
+if [ -z "${KOKORO_BUILD_ID}" ]; then
+  if ! gcloud auth application-default print-access-token --quiet > /dev/null; then
+      gcloud auth application-default login
+  fi
+fi
+
+pip install -U keyring keyrings.google-artifactregistry-auth twine cibuildwheel
+
+REPO_DIR=$(mktemp -d)
+echo "Created temporary directory: ${REPO_DIR}"
+
+# Ensure the temporary directory is removed on script exit
+trap 'echo "Cleaning up temporary directory: ${REPO_DIR}"; rm -rf "${REPO_DIR}"' EXIT
+
+if [ "${DRY_RUN}" = "true" ]; then
+  echo "[DRY RUN] Using local Kokoro clone instead of cloning main."
+  SRC_DIR="$(cd "$(dirname "$0")/../.." && pwd)"
+  pushd "${SRC_DIR}"
+  # Get the latest tag or fallback
+  VERSION=$(git tag --sort=-v:refname 2>/dev/null | head -n 1 || true)
+  if [ -z "${VERSION}" ]; then
+    VERSION="0.1.2"
+  fi
+  popd
+else
+  pushd "${REPO_DIR}"
+  git clone https://github.com/cel-expr/cel-python.git
+  cd cel-python
+  # Get the latest version tag
+  VERSION=$(git tag --sort=-v:refname | head -n 1)
+  SRC_DIR="${REPO_DIR}/cel-python"
+  popd
+fi
+
+# Strip initial "v" if present
+VERSION=${VERSION#v}
+echo "Building release for version: ${VERSION}"
+
+TMP_DIR=$(mktemp -d)
+echo "Build directory: ${TMP_DIR}"
+
+# Add trap cleanup for TMP_DIR as well
+trap 'echo "Cleaning up temporary directories: ${REPO_DIR} ${TMP_DIR}"; rm -rf "${REPO_DIR}" "${TMP_DIR}"' EXIT
+
+pushd "${TMP_DIR}"
+
+cp -r "${SRC_DIR}"/{*,.*} . 2>/dev/null || true
+cp "${SRC_DIR}"/release/* . 2>/dev/null || true
+rm -rf cel_expr_python/*_test.py
+
+# Check if pyproject.toml exists before running sed
+if [ -f pyproject.toml ]; then
+  sed -i "" "s/\$VERSION/${VERSION}/g" pyproject.toml || sed -i "s/\$VERSION/${VERSION}/g" pyproject.toml
+fi
+
+echo "Running cibuildwheel: ${CIBWHEEL_BIN}"
+# Default CIBWHEEL_BIN if not set
+if [ -z "${CIBWHEEL_BIN}" ]; then
+  CIBWHEEL_BIN="python3 -m cibuildwheel"
+fi
+${CIBWHEEL_BIN} --platform linux --output-dir dist
+
+if [ "${DRY_RUN}" = "true" ]; then
+  echo "[DRY RUN] Skipping upload to PyPI exit gate."
+else
+  echo "Uploading to OSS Exit Gate for autopush to PyPI..."
+  python3 -m twine upload --repository-url https://us-python.pkg.dev/oss-exit-gate-prod/cel-expr-python--pypi dist/*
+fi
+
+popd
+
+echo "cel-expr-python ${VERSION} built and uploaded for release by OSS Exit Gate."