feat(CLI): Revert from unconditional .env support

lib/cli/conditionally-load-dotenv.js

@@ -2,11 +2,8 @@
 
 'use strict';
 
-const path = require('path');
 const _ = require('lodash');
 const memoizee = require('memoizee');
-const fileExists = require('../utils/fs/fileExists');
-const logDeprecation = require('../utils/logDeprecation');
 
 module.exports = memoizee(
   async (options, configuration) => {
@@ -15,24 +12,6 @@ module.exports = memoizee(
       require('./load-dotenv')(stage);
       return;
     }
-
-    const defaultEnvFilePath = path.resolve('.env');
-    const stageEnvFilePath = path.resolve(`.env.${stage}`);
-
-    const [doesStageEnvFileExists, doesDefaultEnvFileExists] = await Promise.all([
-      fileExists(stageEnvFilePath),
-      fileExists(defaultEnvFilePath),
-    ]);
-
-    if (doesDefaultEnvFileExists || doesStageEnvFileExists) {
-      logDeprecation(
-        'LOAD_VARIABLES_FROM_ENV_FILES',
-        'Detected ".env" files. In the next major release variables from ".env" ' +
-          'files will be automatically loaded into the serverless build process. ' +
-          'Set "useDotenv: true" to adopt that behavior now.',
-        { serviceConfig: configuration }
-      );
-    }
   },
   {
     length: 0 /* Intentionally no "promise: true" as rejection means critical non-retryable error */,