[llvm] [NFC][IR2Vec] Increasing tolerance in `approximatelyEquals()` of `Embedding` (PR #145117)

[S. VenkataKeerthy via llvm-commits]

svkeerthy wrote:

### Merge activity

* **Jul 1, 7:02 PM UTC**: A user started a stack merge that includes this pull request via [Graphite](https://app.graphite.dev/github/pr/llvm/llvm-project/145117).


https://github.com/llvm/llvm-project/pull/145117