Merge bitcoin/bitcoin#26742: http: Track active requests and wait for last to finish - 2nd attempt

60978c8080 test: Reduce extended timeout on abortnode test (Fabian Jahr)
660bdbf785 http: Release server before waiting for event base loop exit (João Barbosa)
8c6d007c80 http: Track active requests and wait for last to finish (João Barbosa)

Pull request description:

  This revives #19420. Since promag is not so active at the moment, I can support this to finally get it merged.

  The PR is rebased and comments by jonatack have been addressed.

  Once this is merged, I will also reopen #19434.

ACKs for top commit:
  achow101:
    ACK 60978c8080
  stickies-v:
    re-ACK [60978c8](60978c8080)
  hebasto:
    ACK 60978c8080

Tree-SHA512: eef0fe1081e9331b95cfafc71d82f2398abd1d3439dac5b2fa5c6d9c0a3f63ef19adde1c38c88d3b4e7fb41ce7c097943f1815c10e33d165918ccbdec512fe1c

test/functional/feature_abortnode.py

@@ -19,7 +19,6 @@ class AbortNodeTest(BitcoinTestFramework):
     def set_test_params(self):
         self.setup_clean_chain = True
         self.num_nodes = 2
-        self.rpc_timeout = 240
 
     def setup_network(self):
         self.setup_nodes()
@@ -41,7 +40,7 @@ class AbortNodeTest(BitcoinTestFramework):
 
             # Check that node0 aborted
             self.log.info("Waiting for crash")
-            self.nodes[0].wait_until_stopped(timeout=200)
+            self.nodes[0].wait_until_stopped(timeout=5)
         self.log.info("Node crashed - now verifying restart fails")
         self.nodes[0].assert_start_raises_init_error()