Add eigen version from main.

[feuerste]

Version 3.4.0 is 3 years old. This version pulls
in all the functionality added throughout the last years.

[bazel-io]

Hello @bazelbuild/bcr-maintainers, modules without existing maintainers (eigen) have been updated in this PR. Please review the changes.

[meteorcloudy]

The version format change is concerning, assuming there is a 3.5 coming out later, 20241125.0 is actually going to be considered as a newer verison.

[feuerste]

@meteorcloudy I wasn't sure myself how to version it. Do you have a better suggestion? 4.0 should come some time as well, but not much work is going on according to https://gitlab.com/libeigen/eigen/-/issues/2699, https://gitlab.com/libeigen/eigen/-/issues/2845, and https://gitlab.com/libeigen/eigen/-/issues/2848.

[udaya2899]

Considering the latest released version is 3 years old, and the new version is in discussion but no actual plans or dates, we are blocked since our tests depend on a newer version and are failing on an older version.

For now, I don't see a better way than to suggest @feuerste to use the date from when HEAD was cut (i.e. today) to create this.

@feuerste already shared a few issue discussions based on which I suggested to cut from HEAD to get in the newer features that we depend on.

[meteorcloudy]

Indeed, it's a bit tricky, but to be future proof, maybe we can use something like: 3.4.0.20241125? So that it will be the current latest version, but if 3.5.0 or 4.0 come out, it will not mess up the order. If we are sure the next version is going to be 4.0.0, then we can also use 4.0.0-20241125 to indicate this is a pre-release of 4.0.

[meteorcloudy]

Please also fix the directory name

Require module maintainers' approval for newly pushed changes.

[feuerste]

Thanks for your review and suggestions @meteorcloudy !

[meteorcloudy]

Np, one more fix needed ;)

BcrValidationResult.FAILED: The patch file `modules/eigen/4.0.0-20241125/patches/module_dot_bazel.patch` has expected integrity value `sha256-Q9fpY+Y/Z8x2bvDlfI9onJe9FDPF4PkfQxCBvqBmKDk=`, but the real integrity value is `sha256-4R/Q+wbTHHJpkHeb5Ox2wLjIpbqhbnIc9gvfve8FAbA=`.

Require module maintainers' approval for newly pushed changes.