Add environment variables to signal feature and version to the CLI

This PR ensures environment variables are set before any invocation of
the CLI.  Here is a list of vars that are set:

https://github.com/github/codeql-coreql-team/issues/1124#issuecomment-852463521

This ensures the CLI knows the features and versions of the containing
actions/runner.

Additionally:

- Fix the user agent so that it more closely aligns with user agent
  spec
- Refactor environment variable initialization so that it all happens in
  one place and call.
- Move Mode, getRequiredEnvParam, setMode, getMode out of actions-util
  and into util. actions-util is meant for utils only called by the
  action, not the runner.

The `prepareLocalRunEnvironment()` method is most likely deprecated and
should be removed. I originally added it because I had a way of working
where I would run the action from my local machine to test out changes,
but this was always a little flaky. So, I no longer use this way of
working. I will probably remove it soon.

src/analyze-action.ts

@@ -14,6 +14,9 @@ import { getActionsLogger } from "./logging";
 import * as upload_lib from "./upload-lib";
 import * as util from "./util";
 
+// eslint-disable-next-line import/no-commonjs
+const pkg = require("../package.json");
+
 interface AnalysisStatusReport
   extends upload_lib.UploadStatusReport,
     QueriesStatusReport {}
@@ -49,10 +52,9 @@ async function run() {
   const startedAt = new Date();
   let stats: AnalysisStatusReport | undefined = undefined;
   let config: Config | undefined = undefined;
-  actionsUtil.setMode(actionsUtil.Mode.actions);
+  util.initializeEnvironment(util.Mode.actions, pkg.version);
 
   try {
-    actionsUtil.prepareLocalRunEnvironment();
     if (
       !(await actionsUtil.sendStatusReport(
         await actionsUtil.createStatusReportBase(
@@ -65,7 +67,7 @@ async function run() {
       return;
     }
     const logger = getActionsLogger();
-    config = await getConfig(actionsUtil.getTemporaryDirectory(), logger);
+    config = await getConfig(util.getTemporaryDirectory(), logger);
     if (config === undefined) {
       throw new Error(
         "Config file could not be found at expected location. Has the 'init' action been called?"
@@ -74,7 +76,7 @@ async function run() {
 
     const apiDetails = {
       auth: actionsUtil.getRequiredInput("token"),
-      url: actionsUtil.getRequiredEnvParam("GITHUB_SERVER_URL"),
+      url: util.getRequiredEnvParam("GITHUB_SERVER_URL"),
     };
     const outputDir = actionsUtil.getRequiredInput("output");
     const queriesStats = await runAnalyze(