Exclude search and browse from Angular SSR (#3709)

* [DURACOM-303] prevent possibly long-lasting search and browse calls in SSR

* [DURACOM-303] implement skeleton component for search results

* [DURACOM-303] add skeleton loader for search results and filters

* [DURACOM-303] minor restyle of skeleton for mobile

* [DURACOM-303] fix lint and tests

* [DURACOM-303] adapt tests

* [DURACOM-303] restyle skeleton, add filter badge skeleton

* [DURACOM-303] add loop for filters count

* [DURACOM-303] add grid layout, make SSR enabling configurable, minor restyle of skeletons

* [DURACOM-303] refactor param, add example of configuration

* [DURACOM-303] rename variable, minor code refactor

* [DURACOM-303] add override possibility with input

* [DURACOM-303] fix SSR check on template and on components missing the environment config. Add descriptive comment for skeleton component. Fix JS error on SSR.

* [DURACOM-303] refactor thumbnail's skeleton style

src/environments/environment.test.ts

@@ -13,6 +13,8 @@ export const environment: BuildConfig = {
     enablePerformanceProfiler: false,
     inlineCriticalCss: false,
     paths: [ '/home', '/items/', '/entities/', '/collections/', '/communities/', '/bitstream/', '/bitstreams/', '/handle/' ],
+    enableSearchComponent: false,
+    enableBrowseComponent: false,
   },
 
   // Angular express server settings.