[code] Remove the useless deps download control option (#43940) (#44207)

The `installGoDependency` should be the only way to notify go langserver
to install the deps.

x-pack/legacy/plugins/code/server/lsp/go_launcher.ts

@@ -14,9 +14,9 @@ import { Logger } from '../log';
 import { ServerOptions } from '../server_options';
 import { LoggerFactory } from '../utils/log_factory';
 import { AbstractLauncher } from './abstract_launcher';
+import { ExternalProgram } from './process/external_program';
 import { LanguageServerProxy } from './proxy';
 import { InitializeOptions, RequestExpander } from './request_expander';
-import { ExternalProgram } from './process/external_program';
 
 const GO_LANG_DETACH_PORT = 2091;
 
@@ -98,15 +98,6 @@ export class GoServerLauncher extends AbstractLauncher {
     if (!fs.existsSync(goPath)) {
       fs.mkdirSync(goPath);
     }
-    let go111MODULE = 'off';
-    if (this.options.security.installGoDependency) {
-      // There are no proper approaches to disable downloading go dependencies except creating inconsistencies of the
-      // running environments of go-langserver. Given that go language server will do its best to convert the repos
-      // into modules, one of the doable approaches is setting 'GO111MODULE' to false to be incompatible with the
-      // moduled repos.
-      go111MODULE = 'on';
-    }
-
     const params: string[] = ['-port=' + port.toString()];
     const golsp = path.resolve(installationPath, launchersFound[0]);
     const p = spawn(golsp, params, {
@@ -119,7 +110,6 @@ export class GoServerLauncher extends AbstractLauncher {
         GOROOT: goRoot,
         GOPATH: goPath,
         PATH: envPath,
-        GO111MODULE: go111MODULE,
         CGO_ENABLED: '0',
       },
     });