Fix default argument of gc

Author: Tibowl

src/commands/misc/gachacalc.ts

@@ -143,7 +143,7 @@ Example with 70 pulls, 10 pity and guaranteed for 5 star weapon banner: \`${conf
         const gacha = options.getString("gacha") ?? "char"
         const pulls = options.getInteger("pulls", true)
         const pity = options.getInteger("pity") ?? 0
-        const current = options.getInteger("current") ?? 0
+        const current = options.getInteger("current") ?? -1
         const guaranteedPity = options.getInteger("guaranteedPity") ?? 0
         const guaranteed = options.getBoolean("guaranteed") ?? false