fix: consistent rep interval capitalisation (#2273)

Author: Erotemic

src/i18n/locales/en.json

@@ -2668,7 +2668,7 @@
     "lqi": "LQI",
     "mains_single_phase": "Mains (single phase)",
     "manufacturer": "Manufacturer",
-    "max_rep_interval": "max rep interval",
+    "max_rep_interval": "Max rep interval",
     "min_rep_change": "Min rep change",
     "min_rep_interval": "Min rep interval",
     "model": "Model",