Pin `latest` to a specific version for arm64-linux

Fixes: #1040

emscripten-releases-tags.json

diff --git a/emscripten-releases-tags.json b/emscripten-releases-tags.json
index e522911..d509cdd 100644
--- a/emscripten-releases-tags.json
+++ b/emscripten-releases-tags.json
@@ -2,6 +2,7 @@
   "aliases": {
     "latest": "3.1.14",
     "latest-sdk": "latest",
+    "latest-arm64-linux": "3.1.9",
     "latest-64bit": "latest",
     "sdk-latest-64bit": "latest",
     "latest-upstream": "latest",

emsdk.py

diff --git a/emsdk.py b/emsdk.py
index 1b5fc79..39ff4c5 100644
--- a/emsdk.py
+++ b/emsdk.py
@@ -2186,6 +2186,9 @@
 
 def resolve_sdk_aliases(name, verbose=False):
   releases_info = load_releases_info()
+  if name == 'latest' and LINUX and ARCH == 'aarch64':
+    print("warning: 'latest' on arm64-linux may be slightly behind other architectures")
+    name = 'latest-arm64-linux'
   while name in releases_info['aliases']:
     if verbose:
       print("Resolving SDK alias '%s' to '%s'" % (name, releases_info['aliases'][name]))