app playground: using search service make it the default tab

[rubenfiszel]

if using the search service then upon opening of the app playground, instead of seeing the explorer tab, it defaults to the search tab:

This is confusing. I couldn't find where to set it. It's more of a vscode issue than it is a monaco-languageclient issue.

Relevant wrapper config:

				serviceOverrides: {
					...getConfigurationServiceOverride(),
					...getKeybindingsServiceOverride(),
					...getLifecycleServiceOverride(),
					...getSearchServiceOverride(),
					...getExplorerServiceOverride()

				},

				viewsConfig: {
					viewServiceType: 'ViewsService',
					viewsInitFunc: defaultViewsInit
				},