docs(popover): add ion-content wrappers for consistent rendering across frameworks

Author: amandaesmith333

static/usage/popover/presenting/inline-isopen/react.md

@@ -12,12 +12,12 @@ function Example() {
   };
 
   return (
-    <>
+    <IonContent>
       <IonButton onClick={openPopover}>Click Me</IonButton>
       <IonPopover ref={popover} isOpen={popoverOpen} onDidDismiss={() => setPopoverOpen(false)}>
         <IonContent class="ion-padding">Hello World!</IonContent>
       </IonPopover>
-    </>
+    </IonContent>
   );
 }
 export default Example;

static/usage/popover/presenting/inline-isopen/vue.md

@@ -1,13 +1,15 @@
 ```html
 <template>
-  <ion-button @click="openPopover($event)">Click Me</ion-button>
-  <ion-popover
-    :is-open="popoverOpen"
-    :event="event"
-    @didDismiss="popoverOpen = false"
-  >
-    <ion-content class="ion-padding">Hello World!</ion-content>
-  </ion-popover>
+  <ion-content>
+    <ion-button @click="openPopover($event)">Click Me</ion-button>
+    <ion-popover
+      :is-open="popoverOpen"
+      :event="event"
+      @didDismiss="popoverOpen = false"
+    >
+      <ion-content class="ion-padding">Hello World!</ion-content>
+    </ion-popover>
+  </ion-content>
 </template>
 
 <script lang="ts">