Only display docs enterprise upsell on official mempool

frontend/src/app/docs/api-docs/api-docs-nav.component.html

@@ -1,4 +1,4 @@
-<div id="enterprise-cta-desktop">
+<div id="enterprise-cta-desktop" *ngIf="officialMempoolInstance">
   <p>Get higher API limits with Mempool Enterprise®</p>
   <a class="btn btn-small btn-purple" href="/enterprise">More Info <fa-icon [icon]="['fas', 'angle-right']" [styles]="{'font-size': '12px'}"></fa-icon></a>
 </div>

frontend/src/app/docs/api-docs/api-docs.component.html

@@ -39,7 +39,7 @@
 
       <div class="doc-content">
 
-        <div id="enterprise-cta-mobile" *ngIf="showMobileEnterpriseUpsell">
+        <div id="enterprise-cta-mobile" *ngIf="officialMempoolInstance && showMobileEnterpriseUpsell">
           <p>Get higher API limits with <span class="no-line-break">Mempool Enterprise®</span></p>
           <div class="button-group">
             <a class="btn btn-small btn-secondary" (click)="showMobileEnterpriseUpsell = false">No Thanks</a>