Prevent .curlrc from being loaded.

Library/Homebrew/cmd/vendor-install.sh

@@ -48,6 +48,7 @@ fetch() {
   local temporary_path
 
   curl_args=(
+    -q # do not load .curlrc (must be the first argument)
     --fail
     --remote-time
     --location

Library/Homebrew/test/utils/curl_spec.rb

@@ -0,0 +1,10 @@
+require "utils/curl"
+
+describe "curl" do
+  describe "curl_args" do
+    it "returns -q as the first argument" do
+      # -q must be the first argument according to "man curl"
+      expect(curl_args("foo")[1]).to eq("-q")
+    end
+  end
+end

Library/Homebrew/utils/curl.rb

@@ -14,6 +14,7 @@ end
 def curl_args(*extra_args, show_output: false, user_agent: :default)
   args = [
     curl_executable.to_s,
+    "-q", # do not load .curlrc (must be the first argument)
     "--show-error",
   ]