Set EMSDK_PYTHON directly

Author: kon72

bazel/emscripten_toolchain/env.bat

@@ -3,4 +3,3 @@
 set ROOT_DIR=%CD%
 set EMSCRIPTEN=%ROOT_DIR%\%EM_BIN_PATH%\emscripten
 set EM_CONFIG=%ROOT_DIR%\%EM_CONFIG_PATH%
-set EMSDK_PYTHON=%ROOT_DIR%\%EM_PYTHON_PATH%

bazel/emscripten_toolchain/env.sh

@@ -3,4 +3,3 @@
 export ROOT_DIR=${EXT_BUILD_ROOT:-$(pwd -P)}
 export EMSCRIPTEN=$ROOT_DIR/$EM_BIN_PATH/emscripten
 export EM_CONFIG=$ROOT_DIR/$EM_CONFIG_PATH
-export EMSDK_PYTHON=$ROOT_DIR/$EM_PYTHON_PATH

bazel/emscripten_toolchain/toolchain.bzl

@@ -1041,7 +1041,7 @@ def _impl(ctx):
                     value = ctx.file.em_config.path,
                 ),
                 env_entry(
-                    key = "EM_PYTHON_PATH",
+                    key = "EMSDK_PYTHON",
                     value = ctx.file._python_interpreter.path,
                 ),
             ],