Merge bitcoin/bitcoin#26714: test: add coverage for unparsable -maxuploadtarget

7a83aa0982 test: add coverage for unparsable `-maxuploadtarget` (brunoerg)

Pull request description:

  This PR adds test coverage for the following error:
  https://github.com/bitcoin/bitcoin/blob/7386da7a0b08cd2df8ba88dae1fab9d36424b15c/src/init.cpp#L1096-L1099

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Tree-SHA512: c115b2b4d2d0eb2316bf9fafd7e0046aa18c9650062779b3a82d6145d188765bff5317f4ca5f79607732fde6d83e1f67756ac20a12c98d060ee68d8acc20c76e

test/functional/feature_maxuploadtarget.py

@@ -164,6 +164,9 @@ class MaxUploadTest(BitcoinTestFramework):
         assert_equal(len(peer_info), 1)  # node is still connected
         assert_equal(peer_info[0]['permissions'], ['download'])
 
+        self.log.info("Test passing an unparsable value to -maxuploadtarget throws an error")
+        self.stop_node(0)
+        self.nodes[0].assert_start_raises_init_error(extra_args=["-maxuploadtarget=abc"], expected_msg="Error: Unable to parse -maxuploadtarget: 'abc'")
 
 if __name__ == '__main__':
     MaxUploadTest().main()