chore: rollback loki-fluent bit (#135)

try and unblock staging. This was the last change that would affect only
staging/prod and not PR builds that i can thing of.

PR builds also create a brand new set of resources every time, while
staging is trying to do an update, so this may have nothing to do with
it.

License: MIT

Signed-off-by: Oli Evans <oli@protocol.ai>

stacks/PickupStack.ts

@@ -110,7 +110,7 @@ export function PickupStack ({ app, stack }: StackContext): void {
       firelensConfig: {
         type: FirelensLogRouterType.FLUENTBIT
       },
-      image: ContainerImage.fromRegistry('grafana/fluent-bit-plugin-loki:2.7.4-amd64')
+      image: ContainerImage.fromRegistry('grafana/fluent-bit-plugin-loki:1.6.0-amd64')
     })
   }
 }