docs: update patch testing instructions (#5543)

* docs: explain how to test exec-argv

* docs: explain how to test telemetry patch

patches/exec-argv.diff

@@ -1,6 +1,13 @@
 Preserve process.execArgv
 
-This ensures flags like --prof are passed down so we can profile everything.
+This ensures flags like `--prof` are passed down to the code-server process so
+we can profile everything.
+
+To test this:
+1. run `./lib/node --prof .` 
+2. in another terminal, run `ps -ejww`
+
+You should see `--prof` next to every code-server process. 
 
 Index: code-server/lib/vscode/src/vs/server/node/extensionHostConnection.ts
 ===================================================================

patches/telemetry.diff

@@ -2,6 +2,11 @@ Add support for telemetry endpoint
 
 Contains some fixes included in https://github.com/microsoft/vscode/commit/b108bc8294ce920fcf2ee8d53f97c3bcf3316e1c
 
+To test:
+1. Look inside a build of code-server, inside `lib/vscode/vs/server/node/server.main.js`
+2. Search for a `JSON.stringify` near `TelemetryClient`
+3. throw in a `console.log()` before it and make sure it logs telemetry data
+
 Index: code-server/lib/vscode/src/vs/server/node/serverServices.ts
 ===================================================================
 --- code-server.orig/lib/vscode/src/vs/server/node/serverServices.ts