[google-cloud-cpp-spanner] Add new port (microsoft#9096)

* [google-cloud-cpp-spanner] New port

A client library for Google's Cloud Spanner.

* Fix package version.

ports/google-cloud-cpp-spanner/CONTROL

@@ -0,0 +1,5 @@
+Source: google-cloud-cpp-spanner
+Version: 0.3.0
+Build-Depends: grpc, curl[ssl], crc32c, googleapis, google-cloud-cpp-common
+Description: C++ Client Library for Google Cloud Spanner.
+Homepage: https://github.com/googleapis/google-cloud-cpp-spanner

ports/google-cloud-cpp-spanner/portfile.cmake

@@ -0,0 +1,31 @@
+include(vcpkg_common_functions)
+
+vcpkg_check_linkage(ONLY_STATIC_LIBRARY)
+
+vcpkg_from_github(
+    OUT_SOURCE_PATH SOURCE_PATH
+    REPO googleapis/google-cloud-cpp-spanner
+    REF v0.3.0
+    SHA512 8148a78b83770d38d4ad9ce3c4e7229920b731c2150214bdd0e89a94d1d0d618322f36cb7e8cd0cb0281ee3dae328b87cac5ccd25cb36bef5762cc5c93921616
+    HEAD_REF master
+)
+
+vcpkg_configure_cmake(
+    SOURCE_PATH ${SOURCE_PATH}
+    PREFER_NINJA
+    DISABLE_PARALLEL_CONFIGURE
+    OPTIONS
+        -DGOOGLE_CLOUD_CPP_ENABLE_MACOS_OPENSSL_CHECK=OFF
+        -DBUILD_TESTING=OFF
+)
+
+vcpkg_install_cmake(ADD_BIN_TO_PATH)
+
+file(REMOVE_RECURSE
+    ${CURRENT_PACKAGES_DIR}/debug/include
+    ${CURRENT_PACKAGES_DIR}/debug/share)
+vcpkg_fixup_cmake_targets(CONFIG_PATH lib/cmake TARGET_PATH share)
+
+file(INSTALL ${SOURCE_PATH}/LICENSE DESTINATION ${CURRENT_PACKAGES_DIR}/share/google-cloud-cpp-spanner RENAME copyright)
+
+vcpkg_copy_pdbs()