fix(insights): avoid using the default transaction.op filter in the transaction summary (#95436)

In eap, blank transaction ops are set to `default` but in non-eap they
are just empty strings. On the insights overview page, there was an
issue where clicking on a transaction with op of `default` would yield
no results on the transaction summary page. This is because we
automatically applied a `transaction.op:default` filter, but the summary
page is not eap yet.

This PR remove the transaction.op filter when navigating to the summary
page if the op is `default`. This is only done on backend and mobile
overview pages because the frontend page does not group by op

Author: DominikB2014

static/app/views/insights/pages/backend/backendTable.tsx

@@ -221,11 +221,15 @@ function renderBodyCell(
   }
 
   if (column.key === 'transaction') {
+    // In eap, blank transaction ops are set to `default` but not in non-eap.
+    // The transaction summary is not eap yet, so we should exclude the `default` transaction.op filter
+    const spanOp =
+      row['span.op'].toLowerCase() === 'default' ? undefined : row['span.op'];
     return (
       <TransactionCell
         project={row.project}
         transaction={row.transaction}
-        transactionMethod={row['span.op']}
+        transactionMethod={spanOp}
       />
     );
   }

static/app/views/insights/pages/mobile/mobileOverviewTable.tsx

@@ -203,11 +203,15 @@ function renderBodyCell(
   }
 
   if (column.key === 'transaction') {
+    // In eap, blank transaction ops are set to `default` but not in non-eap.
+    // The transaction summary is not eap yet, so we should exclude the `default` transaction.op filter
+    const spanOp =
+      row['span.op'].toLowerCase() === 'default' ? undefined : row['span.op'];
     return (
       <TransactionCell
         project={row.project}
         transaction={row.transaction}
-        transactionMethod={row['span.op']}
+        transactionMethod={spanOp}
       />
     );
   }