tests: Skip unnecessary fuzzer initialisation. Hold ECCVerifyHandle only when needed.

src/test/fuzz/deserialize.cpp

@@ -12,6 +12,7 @@
 #include <net.h>
 #include <primitives/block.h>
 #include <protocol.h>
+#include <pubkey.h>
 #include <streams.h>
 #include <undo.h>
 #include <version.h>
@@ -23,6 +24,12 @@
 
 #include <test/fuzz/fuzz.h>
 
+void initialize()
+{
+    // Fuzzers using pubkey must hold an ECCVerifyHandle.
+    static const auto verify_handle = MakeUnique<ECCVerifyHandle>();
+}
+
 void test_one_input(const std::vector<uint8_t>& buffer)
 {
     CDataStream ds(buffer, SER_NETWORK, INIT_PROTO_VERSION);