rpc: drop unneeded IsRPCRunning() guards

This was preventing the (hidden) waitfornewblock, waitforblock and
waitforblockheight methods from being used in the GUI.

The check was added in d6a5dc4
when these RPC methods were first introduced.

They could have been dropped when dca9231
refactored these methods to use waitTipChanged(), which already
checks for shutdown.

Making this change now simplifies the next commit.

Author: Sjors

src/rpc/blockchain.cpp

@@ -287,9 +287,7 @@ static RPCHelpMan waitfornewblock()
     Mining& miner = EnsureMining(node);
 
     auto block{CHECK_NONFATAL(miner.getTip()).value()};
-    if (IsRPCRunning()) {
-        block = timeout ? miner.waitTipChanged(block.hash, std::chrono::milliseconds(timeout)) : miner.waitTipChanged(block.hash);
-    }
+    block = timeout ? miner.waitTipChanged(block.hash, std::chrono::milliseconds(timeout)) : miner.waitTipChanged(block.hash);
 
     UniValue ret(UniValue::VOBJ);
     ret.pushKV("hash", block.hash.GetHex());
@@ -334,7 +332,7 @@ static RPCHelpMan waitforblock()
 
     auto block{CHECK_NONFATAL(miner.getTip()).value()};
     const auto deadline{std::chrono::steady_clock::now() + 1ms * timeout};
-    while (IsRPCRunning() && block.hash != hash) {
+    while (block.hash != hash) {
         if (timeout) {
             auto now{std::chrono::steady_clock::now()};
             if (now >= deadline) break;
@@ -390,7 +388,7 @@ static RPCHelpMan waitforblockheight()
     auto block{CHECK_NONFATAL(miner.getTip()).value()};
     const auto deadline{std::chrono::steady_clock::now() + 1ms * timeout};
 
-    while (IsRPCRunning() && block.height < height) {
+    while (block.height < height) {
         if (timeout) {
             auto now{std::chrono::steady_clock::now()};
             if (now >= deadline) break;