Revert "fix tests for electron downgrade"

This reverts commit d2a0075.

Author: flotwig

packages/server/__snapshots__/8_reporters_spec.coffee.js

@@ -697,7 +697,6 @@ Error: this reporter threw an error
     at stack trace line
     at stack trace line
     at stack trace line
-    at stack trace line
 
 Learn more at https://on.cypress.io/reporters
 

packages/server/test/integration/cypress_spec.coffee

@@ -774,12 +774,12 @@ describe "lib/cypress", ->
           debugger: {
             on: sinon.stub()
             attach: sinon.stub()
-            sendCommand: sinon.stub().callsArg(2)
+            sendCommand: sinon.stub().resolves()
           }
           setUserAgent: sinon.stub()
           session: {
-            clearCache: sinon.stub().yieldsAsync()
-            setProxy: sinon.stub().yieldsAsync()
+            clearCache: sinon.stub().resolves()
+            setProxy: sinon.stub().resolves()
             setUserAgent: sinon.stub()
           }
         }

packages/server/test/unit/browsers/electron_spec.coffee

@@ -348,7 +348,7 @@ describe "lib/browsers/electron", ->
     it "sets proxy rules for webContents", ->
       webContents = {
         session: {
-          setProxy: sinon.stub().callsArg(1)
+          setProxy: sinon.stub().resolves()
         }
       }
 
@@ -366,6 +366,8 @@ describe "lib/browsers/electron", ->
       @sendCommand.throws()
       .withArgs('Browser.getVersion').resolves()
 
+      electron._attachDebugger(@win.webContents)
+
       @onRequest = electron._getAutomation(@win).onRequest
 
     describe "get:cookies", ->