Fix the calculation for estimated gas price

The gas price returned by the rpc is base_fee + max_priority_fee.
So we shouldn't add the max_priority_fee onto that value since it's
already included. Also the logic used by viem for applying the
multiplier is to only apply the multiplier to the base fee and not the
priority fee, so we match that approach here.

src/celo/fees.test.ts

@@ -45,9 +45,11 @@ describe('celo/fees', () => {
       },
     } as any)
 
+    // The fees maxFeePerGas is calculated as (baseFee * multiplier) + maxPriorityFeePerGas
+    // Which is ((15057755162-602286) * 150 / 100) + 602286 = 22586331600
     expect(fees).toMatchInlineSnapshot(`
         {
-          "maxFeePerGas": 22587235029n,
+          "maxFeePerGas": 22586331600n,
           "maxPriorityFeePerGas": 602286n,
         }
       `)

src/celo/fees.ts

@@ -30,11 +30,10 @@ export const fees: ChainFees<typeof formatters> = {
       ),
     ])
 
-    const suggestedMaxFeePerGas =
-      params.multiply(maxFeePerGas) + maxPriorityFeePerGas
+    const adjustedBasFee = params.multiply(maxFeePerGas-maxPriorityFeePerGas)
 
     return {
-      maxFeePerGas: suggestedMaxFeePerGas,
+      maxFeePerGas: adjustedBasFee + maxPriorityFeePerGas,
       maxPriorityFeePerGas,
     }
   },