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.

lib/codeql.test.js

@@ -14,12 +14,12 @@ const path = __importStar(require("path"));
 const toolcache = __importStar(require("@actions/tool-cache"));
 const ava_1 = __importDefault(require("ava"));
 const nock_1 = __importDefault(require("nock"));
-const actions_util_1 = require("./actions-util");
 const codeql = __importStar(require("./codeql"));
 const defaults = __importStar(require("./defaults.json"));
 const logging_1 = require("./logging");
 const testing_utils_1 = require("./testing-utils");
 const util = __importStar(require("./util"));
+const util_1 = require("./util");
 testing_utils_1.setupTests(ava_1.default);
 const sampleApiDetails = {
     auth: "token",
@@ -30,7 +30,7 @@ const sampleGHAEApiDetails = {
     url: "https://example.githubenterprise.com",
 };
 ava_1.default.beforeEach(() => {
-    actions_util_1.setMode(actions_util_1.Mode.actions);
+    util_1.initializeEnvironment(util_1.Mode.actions, "1.2.3");
 });
 ava_1.default("download codeql bundle cache", async (t) => {
     await util.withTmpDir(async (tmpDir) => {
@@ -190,12 +190,12 @@ ava_1.default("getExtraOptions throws for bad content", (t) => {
     t.throws(() => codeql.getExtraOptions({ foo: 87 }, ["foo"], []));
     t.throws(() => codeql.getExtraOptions({ "*": [42], foo: { "*": 87, bar: [99] } }, ["foo", "bar"], []));
 });
-ava_1.default.only("getCodeQLActionRepository", (t) => {
+ava_1.default("getCodeQLActionRepository", (t) => {
     const logger = logging_1.getRunnerLogger(true);
-    actions_util_1.setMode(actions_util_1.Mode.actions);
+    util_1.initializeEnvironment(util_1.Mode.actions, "1.2.3");
     const repoActions = codeql.getCodeQLActionRepository(logger);
     t.deepEqual(repoActions, "github/codeql-action");
-    actions_util_1.setMode(actions_util_1.Mode.runner);
+    util_1.initializeEnvironment(util_1.Mode.runner, "1.2.3");
     // isRunningLocalAction() === true
     delete process.env["GITHUB_ACTION_REPOSITORY"];
     process.env["RUNNER_TEMP"] = path.dirname(__dirname);