[MM-14093] Rename 'team' to 'server' and 'tab' to 'view' in most cases, some additional cleanup (#2711)

* Rename MattermostTeam -> UniqueServer, MattermostTab -> UniqueView

* Rename 'team' to 'server'

* Some further cleanup

* Rename weirdly named function

* Rename 'tab' to 'view' in most instances

* Fix i18n

* PR feedback

e2e/specs/deep_linking/deeplink.test.js

@@ -46,7 +46,7 @@ describe('application', function desc() {
                 return window.getBrowserViews().find((view) => view.webContents.id === id).webContents.getURL();
             }, webContentsId);
             isActive.should.equal('https://github.com/test/url');
-            const dropdownButtonText = await mainWindow.innerText('.TeamDropdownButton');
+            const dropdownButtonText = await mainWindow.innerText('.ServerDropdownButton');
             dropdownButtonText.should.equal('github');
             await this.app.close();
         });