Unify tooltip options across visualizations (#33892)

* Unify tooltip options across visualizations

* Update tests

* use addTooltipOptions in piechart

Co-authored-by: Oscar Kilhed <oscar.kilhed@grafana.com>

devenv/dev-dashboards/panel-graph/graph-shared-tooltips.json

@@ -93,7 +93,7 @@
           "displayMode": "list",
           "placement": "bottom"
         },
-        "tooltipOptions": {
+        "tooltip": {
           "mode": "single"
         }
       },
@@ -206,7 +206,7 @@
           "displayMode": "list",
           "placement": "bottom"
         },
-        "tooltipOptions": {
+        "tooltip": {
           "mode": "single"
         }
       },
@@ -352,7 +352,7 @@
           "displayMode": "list",
           "placement": "bottom"
         },
-        "tooltipOptions": {
+        "tooltip": {
           "mode": "single"
         }
       },
@@ -450,7 +450,7 @@
           "displayMode": "list",
           "placement": "bottom"
         },
-        "tooltipOptions": {
+        "tooltip": {
           "mode": "single"
         }
       },
@@ -562,7 +562,7 @@
           "displayMode": "list",
           "placement": "bottom"
         },
-        "tooltipOptions": {
+        "tooltip": {
           "mode": "single"
         }
       },