feat(installer): add github token support

This adds support for utilizing the env var GITHUB_TOKEN when the --auth
flag is passed for both curl/wget download utils. The command
invocations are not included in xtrace output so that the token is not
logged.

fixes #2664

Author: jpeeler

www/install.sh

@@ -20,6 +20,7 @@ USAGE:
 FLAGS:
     -h, --help      Display this message
     -f, --force     Force overwriting an existing binary
+    -a, --auth      Authenticate downloads from Github using GITHUB_TOKEN
 
 OPTIONS:
     --tag TAG       Tag (version) of the crate to install, defaults to latest release
@@ -55,16 +56,35 @@ download() {
   url="$1"
   output="$2"
 
-  if command -v curl > /dev/null; then
-    curl --proto =https --tlsv1.2 -sSfL "$url" "-o$output"
+  if [ "$auth" = false ]; then
+    if command -v curl > /dev/null; then
+      curl --proto =https --tlsv1.2 -sSfL "$url" -o"$output"
+    else
+      wget --https-only --secure-protocol=TLSv1_2 --quiet "$url" -O"$output"
+    fi
   else
-    wget --https-only --secure-protocol=TLSv1_2 --quiet "$url" "-O$output"
+    debug_mode=$(set +o | grep xtrace)
+    set +x
+
+    if command -v curl > /dev/null; then
+      curl --proto =https --tlsv1.2 -sSfL -H "Authorization: Bearer $GITHUB_TOKEN" "$url" -o"$output"
+    else
+      wget --https-only --secure-protocol=TLSv1_2 --quiet --header="Authorization: Bearer $GITHUB_TOKEN" "$url" -O"$output"
+    fi
+
+    if echo "$debug_mode" | grep -q "set -o xtrace"; then
+      set -x
+    fi
   fi
 }
 
+auth=false
 force=false
 while test $# -gt 0; do
   case $1 in
+    --auth| -a)
+      auth=true
+      ;;
     --force | -f)
       force=true
       ;;