fix: expire triggers that are too far into the future (#5646)

## Issue being fixed or feature implemented
`gobject count all`

before:
>Governance Objects: 1195 (Proposals: 9, Triggers: 1186, Other: 0;
Erased: 1), Votes: 135064

after (in 10-ish minutes after gov sync is done):
>Governance Objects: 11 (Proposals: 9, Triggers: 2, Other: 0; Erased:
1), Votes: 702

I _think_ it happens when a node can't follow the right chain for some
reason but it keeps receiving triggers and votes from other nodes which
means triggers never expire on such node. This wouldn't be a problem for
us if we wouldn't reorg testnet/devnets from time to time. Once we reorg
the stuck node happily spams us with all the triggers it saved in the
meantime.

## What was done?
2 sb cycles into the future should be enough for all legit triggers,
drop the ones that have their height even higher

## How Has This Been Tested?
run a node, check rpc

## Breaking Changes
n/a

## Checklist:
- [x] I have performed a self-review of my own code
- [ ] I have commented my code, particularly in hard-to-understand areas
- [ ] I have added or updated relevant unit/integration/functional/e2e
tests
- [ ] I have made corresponding changes to the documentation
- [x] I have assigned this pull request to a milestone _(for repository
code-owners and collaborators only)_

src/governance/classes.cpp

@@ -127,7 +127,7 @@ bool CGovernanceTriggerManager::AddNewTrigger(uint256 nHash)
 
     mapTrigger.insert(std::make_pair(nHash, pSuperblock));
 
-    return true;
+    return !pSuperblock->IsExpired(*governance);
 }
 
 /**
@@ -724,6 +724,14 @@ bool CSuperblock::IsExpired(const CGovernanceManager& governanceManager) const
         return true;
     }
 
+    if (Params().NetworkIDString() != CBaseChainParams::MAIN) {
+        // NOTE: this can happen on testnet/devnets due to reorgs, should never happen on mainnet
+        if (governanceManager.GetCachedBlockHeight() + Params().GetConsensus().nSuperblockCycle * 2 < nBlockHeight) {
+            LogPrint(BCLog::GOBJECT, "CSuperblock::IsExpired -- Trigger is too far into the future\n");
+            return true;
+        }
+    }
+
     return false;
 }
 

src/governance/governance.cpp

@@ -1203,8 +1203,8 @@ int CGovernanceManager::RequestGovernanceObjectVotes(Span<CNode*> vNodesCopy, CC
 
         if (mapObjects.empty()) return -2;
 
-        for (const auto& objPair : mapObjects) {
+        for (const auto& [nHash, govobj] : mapObjects) {
-            uint256 nHash = objPair.first;
+            if (govobj.IsSetCachedDelete()) continue;
             if (mapAskedRecently.count(nHash)) {
                 auto it = mapAskedRecently[nHash].begin();
                 while (it != mapAskedRecently[nHash].end()) {
@@ -1217,7 +1217,7 @@ int CGovernanceManager::RequestGovernanceObjectVotes(Span<CNode*> vNodesCopy, CC
                 if (mapAskedRecently[nHash].size() >= nPeersPerHashMax) continue;
             }
 
-            if (objPair.second.GetObjectType() == GovernanceObject::TRIGGER) {
+            if (govobj.GetObjectType() == GovernanceObject::TRIGGER) {
                 vTriggerObjHashes.push_back(nHash);
             } else {
                 vOtherObjHashes.push_back(nHash);