refactor(composer): use update for lock file maintenance (#12185)

lib/manager/composer/__snapshots__/artifacts.spec.ts.snap

@@ -73,7 +73,7 @@ Array [
 exports[`manager/composer/artifacts performs lockFileMaintenance 1`] = `
 Array [
   Object {
-    "cmd": "composer install --ignore-platform-reqs --no-ansi --no-interaction --no-scripts --no-autoloader --no-plugins",
+    "cmd": "composer update --ignore-platform-reqs --no-ansi --no-interaction --no-scripts --no-autoloader --no-plugins",
     "options": Object {
       "cwd": "/tmp/github/some/repo",
       "encoding": "utf-8",

lib/manager/composer/artifacts.ts

@@ -10,7 +10,6 @@ import * as datasourcePackagist from '../../datasource/packagist';
 import { logger } from '../../logger';
 import { ExecOptions, exec } from '../../util/exec';
 import {
-  deleteLocalFile,
   ensureCacheDir,
   ensureLocalDir,
   getSiblingFileName,
@@ -102,10 +101,6 @@ export async function updateArtifacts({
       ...config.constraints,
     };
 
-    if (config.isLockFileMaintenance) {
-      await deleteLocalFile(lockFileName);
-    }
-
     const preCommands: string[] = [
       `install-tool composer ${await getComposerConstraint(constraints)}`,
     ];
@@ -126,7 +121,7 @@ export async function updateArtifacts({
     const cmd = 'composer';
     let args: string;
     if (config.isLockFileMaintenance) {
-      args = 'install';
+      args = 'update';
     } else {
       args =
         (
@@ -166,7 +161,7 @@ export async function updateArtifacts({
       return res;
     }
 
-    logger.debug(`Commiting vendor files in ${vendorDir}`);
+    logger.debug(`Committing vendor files in ${vendorDir}`);
     for (const f of [...status.modified, ...status.not_added]) {
       if (f.startsWith(vendorDir)) {
         res.push({