feat: remove legacy namespaces support

Author: lahirumaramba

entrypoints.json

@@ -1,7 +1,6 @@
 {
   "firebase-admin": {
-    "legacy": true,
-    "typings": "./lib/default-namespace.d.ts",
+    "typings": "./lib/index.d.ts",
     "dist": "./lib/index.js"
   },
   "firebase-admin/app": {

gulpfile.js

@@ -105,22 +105,15 @@ gulp.task('compile_test', function() {
     .pipe(buildTest())
 });
 
-gulp.task('copyTypings', function() {
-  return gulp.src(['src/index.d.ts', 'src/default-namespace.d.ts'])
-    // Add header
-    .pipe(header(banner))
-    .pipe(gulp.dest(paths.build))
-});
-
-gulp.task('compile_all', gulp.series('compile', 'copyTypings', 'compile_test'));
+gulp.task('compile_all', gulp.series('compile', 'compile_test'));
 
 // Regenerates js every time a source file changes
 gulp.task('watch', function() {
   gulp.watch(paths.src.concat(paths.test), { ignoreInitial: false }, gulp.series('compile_all'));
 });
 
 // Build task
-gulp.task('build', gulp.series('cleanup', 'compile', 'copyTypings'));
+gulp.task('build', gulp.series('cleanup', 'compile'));
 
 // Default task
 gulp.task('default', gulp.series('build'));