test: scale IPC mining wait timeouts by timeout_factor

The IPC mining tests (interface_ipc_mining.py) currently use
hardcoded timeouts (e.g., 1000ms, 60000ms) for operations like
waitTipChanged and waiting for block templates. In heavily
loaded CI environments, such as those running sanitizers with
high parallelism, these hardcoded timeouts can be too short,
leading to spurious test failures and brittleness.

This commit multiplies these timeout variables by the test
suite's global `self.options.timeout_factor`. This ensures that
the IPC wait conditions scale appropriately when the test suite
is run with a higher timeout factor, making the tests robust
against slow execution environments.

Addresses CI brittleness observed in bitcoin-core/libmultiprocess#253.

Github-Pull: #34727
Rebased-From: ad75b147b5

test/functional/interface_ipc_mining.py

@@ -110,7 +110,7 @@ class IPCMiningTest(BitcoinTestFramework):
         """Test Mining interface methods."""
         self.log.info("Running Mining interface test")
         block_hash_size = 32
-        timeout = 1000.0 # 1000 milliseconds
+        timeout = 1000.0 * self.options.timeout_factor # 1000 milliseconds
 
         async def async_routine():
             ctx, mining = await make_mining_ctx(self)
@@ -132,7 +132,7 @@ class IPCMiningTest(BitcoinTestFramework):
 
             self.log.debug("interrupt() should abort waitTipChanged()")
             async def wait_for_tip():
-                long_timeout = 60000.0  # 1 minute
+                long_timeout = max(timeout, 60000.0)  # at least 1 minute
                 result = (await mining.waitTipChanged(ctx, newblockref.hash, long_timeout)).result
                 # Unlike a timeout, interrupt() returns an empty BlockRef.
                 assert_equal(len(result.hash), 0)
@@ -172,7 +172,7 @@ class IPCMiningTest(BitcoinTestFramework):
         """Test BlockTemplate interface methods."""
         self.log.info("Running BlockTemplate interface test")
         block_header_size = 80
-        timeout = 1000.0 # 1000 milliseconds
+        timeout = 1000.0 * self.options.timeout_factor
 
         async def async_routine():
             ctx, mining = await make_mining_ctx(self)
@@ -285,7 +285,7 @@ class IPCMiningTest(BitcoinTestFramework):
                 self.log.debug("interruptWait should abort the current wait")
                 async def wait_for_block():
                     new_waitoptions = self.capnp_modules['mining'].BlockWaitOptions()
-                    new_waitoptions.timeout = timeout * 60 # 1 minute wait
+                    new_waitoptions.timeout = max(timeout, 60000.0) # at least 1 minute
                     new_waitoptions.feeThreshold = 1
                     template7 = await mining_wait_next_template(template6, stack, ctx, new_waitoptions)
                     assert template7 is None