Revert "Update .git-blame-ignore-revs for Pack/Unpack move (#152469)" (#152661)

This reverts commit c43c1c0.

Apologies for the noise - I misunderstood how `git blame --ignore-rev`
works. It’s not suitable for large code-move changes and ends up making
`git blame` more confusing rather than cleaner. From the Git
documentation:

> Lines that were changed or added by an ignored commit will be blamed
> on the previous commit that changed that line or nearby lines.

In this case, since so many new lines were added, skipping the commit
causes `git blame` to attribute them to unrelated changes. I had
expected Git to preserve the true origin of the lines while skipping the
move itself - but that is not what happens.

Therefore, I’m reverting this change. Ignoring the commit obscures blame
history rather than improving it.

Author: banach-space

.git-blame-ignore-revs

@@ -143,6 +143,3 @@ a3a007ad5fa20abc90ead4e1030b481bf109b4cf
 b7e332d3f59f567b1999fbcc660d7837cba8e406
 6056f942abe83b05406df8b04e95ec37a3d160b5
 906295b8a31c8dac5aa845864c0bca9f02f86184
-
-# [mlir][tensor][linalg] Move Pack/UnPack Ops to Linalg
-517800e37e8d3a4ee84214bef65e227612c2a98b