<!-- Describe the issue -->

When our chainstate activation sequence fails and we're running the GUI, we ask the user via a question box whether or not they'd like to re-run the sequence with `fReindex = true`. Fun fact: despite the fact that this sequence is wrapped in a while loop, we only run it twice at most.

https://github.com/bitcoin/bitcoin/blob/7ecb309c4ed1bb9ae6b9a12cbb4f083328edc125/src/init.cpp#L1539-L1556

If they answer yes, the sequence will always fail, because a chainstate will have already been initialized in the original run and `InitializeChainstate` will throw a `std::logic_error`:

https://github.com/bitcoin/bitcoin/blob/7ecb309c4ed1bb9ae6b9a12cbb4f083328edc125/src/validation.cpp#L4573-L4594

This always reproduces. To reproduce:
```
gdb ./src/qt/bitcoin-qt
(gdb) b InitializeChainstate
(gdb) # add breakpoint for the "if (!fLoaded && !ShutdownRequested()) {" line
(gdb) r  # should stop at the breakpoint for InitializeChainstate
(gdb) c  # to advance to the breakpoint for the "if (!fLoaded && !ShutdownRequested()) {" line
(gdb) set fLoaded=false
(gdb) c  # should stop at the breakpoint for InitializeChainstate
(gdb) n  # step through InitializeChainstate to see that it throws
```

We expect the re-run of the chainstate activation sequence to not always fail.

struct Params;
}
namespace node {
static constexpr bool DEFAULT_STOPAFTERBLOCKIMPORT{false};
static const unsigned int BLOCKFILE_CHUNK_SIZE = 0x1000000; 
static const unsigned int UNDOFILE_CHUNK_SIZE = 0x100000; 
static const unsigned int MAX_BLOCKFILE_SIZE = 0x8000000; 
extern std::atomic_bool fImporting;
extern std::atomic_bool fReindex;
extern bool fPruneMode;
extern uint64_t nPruneTarget;
using BlockMap = std::unordered_map<uint256, CBlockIndex, BlockHasher>;
struct CBlockIndexWorkComparator {
    bool operator()(const CBlockIndex* pa, const CBlockIndex* pb) const;
};
struct CBlockIndexHeightOnlyComparator {
    
    bool operator()(const CBlockIndex* pa, const CBlockIndex* pb) const;
};
struct PruneLockInfo {
    int height_first{std::numeric_limits<int>::max()}; 
};
/**
 * Maintains a tree of blocks (stored in `m_block_index`) which is consulted
 * to determine where the most-work tip is.
 *
 * This data is used mostly in `CChainState` - information about, e.g.,
 * candidate tips is not maintained here.
 */
class BlockManager