test: update webpack 4 snapshot

test/e2e/__snapshots__/watch-files.test.js.snap.webpack4

@@ -2,6 +2,7 @@
 
 exports[`watchFiles option should not crash if file doesn't exist should reload when file content is changed: console messages 1`] = `
 Array [
+  "[webpack-dev-server] Overlay is enabled for both errors and warnings.",
   "Hey.",
 ]
 `;
@@ -12,6 +13,7 @@ exports[`watchFiles option should not crash if file doesn't exist should reload
 
 exports[`watchFiles option should work with array config should reload when file content is changed: console messages 1`] = `
 Array [
+  "[webpack-dev-server] Overlay is enabled for both errors and warnings.",
   "Hey.",
 ]
 `;
@@ -22,6 +24,7 @@ exports[`watchFiles option should work with array config should reload when file
 
 exports[`watchFiles option should work with object with multiple paths should reload when file content is changed: console messages 1`] = `
 Array [
+  "[webpack-dev-server] Overlay is enabled for both errors and warnings.",
   "Hey.",
 ]
 `;
@@ -32,6 +35,7 @@ exports[`watchFiles option should work with object with multiple paths should re
 
 exports[`watchFiles option should work with object with single path should reload when file content is changed: console messages 1`] = `
 Array [
+  "[webpack-dev-server] Overlay is enabled for both errors and warnings.",
   "Hey.",
 ]
 `;
@@ -56,6 +60,7 @@ Object {
 
 exports[`watchFiles option should work with options {"interval":400,"poll":200} should reload when file content is changed: console messages 1`] = `
 Array [
+  "[webpack-dev-server] Overlay is enabled for both errors and warnings.",
   "Hey.",
 ]
 `;
@@ -80,6 +85,7 @@ Object {
 
 exports[`watchFiles option should work with options {"poll":200} should reload when file content is changed: console messages 1`] = `
 Array [
+  "[webpack-dev-server] Overlay is enabled for both errors and warnings.",
   "Hey.",
 ]
 `;
@@ -104,6 +110,7 @@ Object {
 
 exports[`watchFiles option should work with options {"poll":true} should reload when file content is changed: console messages 1`] = `
 Array [
+  "[webpack-dev-server] Overlay is enabled for both errors and warnings.",
   "Hey.",
 ]
 `;
@@ -128,6 +135,7 @@ Object {
 
 exports[`watchFiles option should work with options {"usePolling":false,"interval":200,"poll":400} should reload when file content is changed: console messages 1`] = `
 Array [
+  "[webpack-dev-server] Overlay is enabled for both errors and warnings.",
   "Hey.",
 ]
 `;
@@ -152,6 +160,7 @@ Object {
 
 exports[`watchFiles option should work with options {"usePolling":false,"poll":200} should reload when file content is changed: console messages 1`] = `
 Array [
+  "[webpack-dev-server] Overlay is enabled for both errors and warnings.",
   "Hey.",
 ]
 `;
@@ -176,6 +185,7 @@ Object {
 
 exports[`watchFiles option should work with options {"usePolling":false,"poll":true} should reload when file content is changed: console messages 1`] = `
 Array [
+  "[webpack-dev-server] Overlay is enabled for both errors and warnings.",
   "Hey.",
 ]
 `;
@@ -200,6 +210,7 @@ Object {
 
 exports[`watchFiles option should work with options {"usePolling":false} should reload when file content is changed: console messages 1`] = `
 Array [
+  "[webpack-dev-server] Overlay is enabled for both errors and warnings.",
   "Hey.",
 ]
 `;
@@ -224,6 +235,7 @@ Object {
 
 exports[`watchFiles option should work with options {"usePolling":true,"interval":200,"poll":400} should reload when file content is changed: console messages 1`] = `
 Array [
+  "[webpack-dev-server] Overlay is enabled for both errors and warnings.",
   "Hey.",
 ]
 `;
@@ -248,6 +260,7 @@ Object {
 
 exports[`watchFiles option should work with options {"usePolling":true,"poll":200} should reload when file content is changed: console messages 1`] = `
 Array [
+  "[webpack-dev-server] Overlay is enabled for both errors and warnings.",
   "Hey.",
 ]
 `;
@@ -272,6 +285,7 @@ Object {
 
 exports[`watchFiles option should work with options {"usePolling":true} should reload when file content is changed: console messages 1`] = `
 Array [
+  "[webpack-dev-server] Overlay is enabled for both errors and warnings.",
   "Hey.",
 ]
 `;
@@ -282,6 +296,7 @@ exports[`watchFiles option should work with options {"usePolling":true} should r
 
 exports[`watchFiles option should work with string and glob should reload when file content is changed: console messages 1`] = `
 Array [
+  "[webpack-dev-server] Overlay is enabled for both errors and warnings.",
   "Hey.",
 ]
 `;
@@ -292,6 +307,7 @@ exports[`watchFiles option should work with string and glob should reload when f
 
 exports[`watchFiles option should work with string and path to directory should reload when file content is changed: console messages 1`] = `
 Array [
+  "[webpack-dev-server] Overlay is enabled for both errors and warnings.",
   "Hey.",
 ]
 `;