tidy-html5 fails to build with CMake 4.0

[renodr]

CMake 4.0 was released on March 28th, and is a lot more strict than previous versions. Because of the changes, it has broken the build process of tidy. A lot of things that were previously warnings are now no longer allowed.

When trying to build this package with CMake 4.0, the first error that you'll see is:

CMake Error at CMakeLists.txt:20 (cmake_minimum_required):
  Compatibility with CMake < 3.5 has been removed from CMake.

  Update the VERSION argument <min> value.  Or, use the <min>...<max> syntax
  to tell CMake that the project requires at least <min> but has been updated
  to work with policies introduced by <max> or earlier.

  Or, add -DCMAKE_POLICY_VERSION_MINIMUM=3.5 to try configuring anyway.


-- Configuring incomplete, errors occurred!

To fix this, I changed Line 20 of CMakeLists.txt to read "cmake_minimum_required (VERSION 2.8.12...4.0)"

After this though, it still failed to build:

-- Detecting CXX compile features - done
-> TIDY_SO_VERSION = 58. This is an EVEN (stable) release.
-- *** Debug Logging is NOT enabled.
-- *** Building support for runtime configuration files.
-- *** Also building DLL library SHARED, version 5.8.0, date 2021.07.10
-- *** Generating man tidy.1 custom commands...
CMake Error at CMakeLists.txt:530 (add_custom_command):
  Exactly one of PRE_BUILD, PRE_LINK, or POST_BUILD must be given.


CMake Error at CMakeLists.txt:538 (add_custom_command):
  Exactly one of PRE_BUILD, PRE_LINK, or POST_BUILD must be given.


CMake Error at CMakeLists.txt:546 (add_custom_command):
  The following keywords are not supported when using
  add_custom_command(TARGET): DEPENDS


-- Configuring incomplete, errors occurred!

I've fixed this locally and will send in a PR shortly. I can confirm that my patch works with CMake 4.0 and CMake 3.30.x.