scripted-diff: Rename overloaded int GetArg to GetIntArg

Improve readability of code, simplify future scripted diff cleanup PRs, and be
more consistent with naming for GetBoolArg.

This will also be useful for replacing runtime settings type checking
with compile time checking.

-BEGIN VERIFY SCRIPT-
git grep -l GetArg | xargs sed -i 's/GetArg(\([^)]*\( [0-9]\+\|-1\|port\|BaseParams().RPCPort()\|Params().GetDefaultPort()\|_TIMEOUT\|Height\|_WORKQUEUE\|_THREADS\|_CONNECTIONS\|LIMIT\|SigOp\|Bytes\|_VERSION\|_AGE\|_CHECKS\|Checks() ? 1 : 0\|_BANTIME\|Cache\|BLOCKS\|LEVEL\|Weight\|Version\|BUFFER\|TARGET\|WEIGHT\|TXN\|TRANSACTIONS\|ADJUSTMENT\|i64\|Size\|nDefault\|_EXPIRY\|HEIGHT\|SIZE\|SNDHWM\|_TIME_MS\)\))/GetIntArg(\1)/g'
-END VERIFY SCRIPT-

Co-authored-by: Hennadii Stepanov <32963518+hebasto@users.noreply.github.com>

src/rpc/blockchain.cpp

@@ -1503,7 +1503,7 @@ RPCHelpMan getblockchaininfo()
         obj.pushKV("pruneheight",        block->nHeight);
 
         // if 0, execution bypasses the whole if block.
-        bool automatic_pruning = (gArgs.GetArg("-prune", 0) != 1);
+        bool automatic_pruning = (gArgs.GetIntArg("-prune", 0) != 1);
         obj.pushKV("automatic_pruning",  automatic_pruning);
         if (automatic_pruning) {
             obj.pushKV("prune_target_size",  nPruneTarget);
@@ -1650,7 +1650,7 @@ UniValue MempoolInfoToJSON(const CTxMemPool& pool)
     ret.pushKV("bytes", (int64_t)pool.GetTotalTxSize());
     ret.pushKV("usage", (int64_t)pool.DynamicMemoryUsage());
     ret.pushKV("total_fee", ValueFromAmount(pool.GetTotalFee()));
-    size_t maxmempool = gArgs.GetArg("-maxmempool", DEFAULT_MAX_MEMPOOL_SIZE) * 1000000;
+    size_t maxmempool = gArgs.GetIntArg("-maxmempool", DEFAULT_MAX_MEMPOOL_SIZE) * 1000000;
     ret.pushKV("maxmempool", (int64_t) maxmempool);
     ret.pushKV("mempoolminfee", ValueFromAmount(std::max(pool.GetMinFee(maxmempool), ::minRelayTxFee).GetFeePerK()));
     ret.pushKV("minrelaytxfee", ValueFromAmount(::minRelayTxFee.GetFeePerK()));