Fix a CSS check warning when flex and hidden are used at the same time

tailwindlabs/tailwindcss-intellisense#959 (comment)

Author: joshk

lib/nerves_hub_web/live/product/insights.html.heex

@@ -69,7 +69,7 @@
               stroke-linejoin="round"
             />
           </svg>
-          <div class="tooltip-content hidden w-max absolute top-0 left-0 z-20 text-xs px-2 py-1.5 rounded border border-[#3F3F46] bg-base-900 flex">
+          <div class="tooltip-content w-max absolute top-0 left-0 z-20 text-xs px-2 py-1.5 rounded border border-[#3F3F46] bg-base-900 hidden">
             Devices which haven't connected in the last 24 hours.
             <div class="tooltip-arrow absolute w-2 h-2 border-[#3F3F46] bg-base-900 origin-center rotate-45"></div>
           </div>
@@ -104,7 +104,7 @@
               stroke-linejoin="round"
             />
           </svg>
-          <div class="tooltip-content hidden w-max absolute top-0 left-0 z-20 text-xs px-2 py-1.5 rounded border border-[#3F3F46] bg-base-900 flex">
+          <div class="tooltip-content w-max absolute top-0 left-0 z-20 text-xs px-2 py-1.5 rounded border border-[#3F3F46] bg-base-900 hidden">
             Over 5 disconnections in the last 24 hours.
             <div class="tooltip-arrow absolute w-2 h-2 border-[#3F3F46] bg-base-900 origin-center rotate-45"></div>
           </div>
@@ -139,7 +139,7 @@
               stroke-linejoin="round"
             />
           </svg>
-          <div class="tooltip-content hidden w-max absolute top-0 left-0 z-20 text-xs px-2 py-1.5 rounded border border-[#3F3F46] bg-base-900 flex">
+          <div class="tooltip-content w-max absolute top-0 left-0 z-20 text-xs px-2 py-1.5 rounded border border-[#3F3F46] bg-base-900 hidden">
             Unique firmware versions installed on devices.
             <div class="tooltip-arrow absolute w-2 h-2 border-[#3F3F46] bg-base-900 origin-center rotate-45"></div>
           </div>