Update emsdk version to 3.1.67 in Bazel configuration

This CL mostly follows the instructions in
https://github.com/emscripten-core/emsdk/blob/main/bazel/README.md.
Even so, there are a few things that are worth mentioning:

1. I tested the changes locally and in my tests
   incompatible_enable_cc_toolchain_resolution bazel flag made no
   difference (e.g. everything builds with or without the flag);
   I still keep it though because instructions say that it should
   be there and it does not cause any harm.
2. I don't think that we still need to patch emsdk to exclude npm
   modules from the toolchain, because it appears that upstream
   already removed those as a toolchain dependency in
   emscripten-core/emsdk#1045.

It's worth noting, that even though I don't think that emsdk patch
is still needed, I actually wasn't able to reproduce the problem
reported in proxy-wasm#149
locally without the emsdk.patch even with the current version of
emsdk used by C++ SDK.

Signed-off-by: Mikhail Krinkin <krinkin.m.u@gmail.com>

.bazelrc

@@ -0,0 +1,9 @@
+# NOTE: incompatible_enable_cc_toolchain_resolution is set by default on Bazel
+# versions 7.0+, see https://github.com/bazelbuild/bazel/issues/7260.
+#
+# emsdk documentation asks to set this flag (see
+# https://github.com/emscripten-core/emsdk/blob/main/bazel/README.md). And even
+# though things seem to work even without this flag, given that this flag
+# enables improved Bazel C++ toolchain resolution method that became the
+# default in newer Bazel version and does not cause problems, we keep it.
+build --incompatible_enable_cc_toolchain_resolution

bazel/dependencies_extra.bzl

@@ -13,7 +13,9 @@
 #  limitations under the License.
 
 load("@emsdk//:emscripten_deps.bzl", "emscripten_deps")
+load("@emsdk//:toolchains.bzl", "register_emscripten_toolchains")
 
 # Requires proxy_wasm_cpp_sdk_dependencies() to be loaded first.
 def proxy_wasm_cpp_sdk_dependencies_extra():
     emscripten_deps()
+    register_emscripten_toolchains()

bazel/repositories.bzl

@@ -19,12 +19,9 @@ def proxy_wasm_cpp_sdk_repositories():
     maybe(
         http_archive,
         name = "emsdk",
-        sha256 = "1ca0ff918d476c55707bb99bc0452be28ac5fb8f22a9260a8aae8a38d1bc0e27",
-        # v3.1.7 with Bazel fixes
-        strip_prefix = "emsdk-0ea8f8a8707070e9a7c83fbb4a3065683bcf1799/bazel",
-        url = "https://github.com/emscripten-core/emsdk/archive/0ea8f8a8707070e9a7c83fbb4a3065683bcf1799.tar.gz",
-        patches = ["@proxy_wasm_cpp_sdk//bazel:emsdk.patch"],
-        patch_args = ["-p2"],
+        sha256 = "0cb0eabd6e3ceb1a970a2363e67f2b1689c2d83fbeae1e75901213c1f84de2e2",
+        strip_prefix = "emsdk-3.1.67/bazel",
+        url = "https://github.com/emscripten-core/emsdk/archive/refs/tags/3.1.67.tar.gz",
     )
 
     maybe(