fix(build-tools): Fix typetests header version format (#25830)

## Description

This PR removes the pre-release/metadata from the current version when
generating the header for typetest files. For example, if the current
version is `1.2.3-foo` the file would be generated with `1.2.3` instead.
This is important since it prevents CI builds from changing the
typetests files unexpectedly.

Author: scottn12

build-tools/packages/build-cli/src/commands/generate/typetests.ts

@@ -16,6 +16,7 @@ import { Flags } from "@oclif/core";
 import { PackageName } from "@rushstack/node-core-library";
 import * as changeCase from "change-case";
 import { readJson } from "fs-extra/esm";
+import { major, minor, patch } from "semver";
 import {
 	type JSDoc,
 	ModuleKind,
@@ -164,6 +165,9 @@ export default class GenerateTypetestsCommand extends PackageCommand<
 				? [buildToolsImport, previousImport]
 				: [previousImport, buildToolsImport];
 
+		// Remove pre-release/metadata from the current version (e.g., "1.2.3-foo" -> "1.2.3")
+		const currentVersionBase = `${major(currentPackageJson.version)}.${minor(currentPackageJson.version)}.${patch(currentPackageJson.version)}`;
+
 		const fileHeader: string[] = [
 			`/*!
  * Copyright (c) Microsoft Corporation and contributors. All rights reserved.
@@ -175,7 +179,7 @@ export default class GenerateTypetestsCommand extends PackageCommand<
  * Generated by flub generate:typetests in @fluid-tools/build-cli.
  *
  * Baseline (previous) version: ${previousPackageJson.version}
- * Current version: ${currentPackageJson.version}
+ * Current version: ${currentVersionBase}
  */
 
 ${imports.join("\n")}