feat: update Playwright config for CI environment and enhance sign-in page styles

frontend/src/app/components/sign-in-page/sign-in-page.css

@@ -51,8 +51,15 @@
   width: 100%;
   max-width: 360px;
 }
+.sign-in-action ::ng-deep .mdc-button__label {
+  display: inline-flex;
+  align-items: center;
+  justify-content: center;
+}
 .sign-in-action fa-icon {
-  display: flex;
+  display: inline-flex;
+  align-items: center;
+  justify-content: center;
   width: 19px;
   height: 19px;
   margin-left: 8px;