AAE-48227 fix label clipping caused by stale positioning styles

Remove leftover top/line-height overrides in multiline-text, display-external-property
and start-task (people widget) styles that were written for the old custom <label>
implementation. These conflicted with Angular Material's native mat-label floating/notch
positioning, causing the label text to be clipped once the widgets were migrated to
mat-label.

Co-authored-by: Cursor <cursoragent@cursor.com>

lib/core/src/lib/form/components/widgets/multiline-text/multiline-text.widget.scss

@@ -8,10 +8,6 @@
         flex-direction: column;
         position: relative;
 
-        .adf-multiline-text-widget-label {
-            top: 20px;
-        }
-
         &--capped textarea.adf-input {
             max-height: 72px;
             overflow-y: auto;

lib/process-services-cloud/src/lib/form/components/widgets/display-external-property/display-external-property.widget.scss

@@ -4,10 +4,6 @@
     &-display-external-property-widget {
         width: 100%;
 
-        .adf-display-external-property-widget-label {
-            top: 20px;
-        }
-
         &-preview {
             word-break: break-all;
         }

lib/process-services/src/lib/task-list/components/start-task/start-task.component.scss

@@ -77,10 +77,6 @@ adf-start-task {
             width: 100%;
         }
 
-        .adf-people-widget-label {
-            line-height: 0;
-        }
-
         .adf-error-container {
             margin-top: -10px;
         }