Add icons for OS Age and Uptime

Closes #1299
Co-authored-by: @theamit-969

config/fastfetch/config.jsonc

@@ -126,13 +126,13 @@
     },
     {
       "type": "command",
-      "key": "  OS Age ",
+      "key": "󱦟 OS Age",
       "keyColor": "magenta",
       "text": "birth_install=$(stat -c %W /); current=$(date +%s); time_progression=$((current - birth_install)); days_difference=$((time_progression / 86400)); echo $days_difference days"
     },
     {
       "type": "uptime",
-      "key": "  Uptime ",
+      "key": "󱫐 Uptime",
       "keyColor": "magenta"
     },
     {