Align tempfile workspace dependencies with root project (#9524)

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## Summary
While working on potential bug fixes with temporary files on Windows (I
think I am currently ecountering the same issue as #2810)
I noticed that sub-workspaces were not all having the same `tempfile`
version. And they were not relying on the cargo root project dependency.
I don't know at all if it was done on purpose or not.
(I also wanted to override the root dependency with a local source but
it was not possible due to sub-workspaces not relying on the same).

The root lockfile already pinned to the `3.14.0`. Some sub-workspaces
were depending on the `3.12.0`, some others on the `3.14.0`. So I
updated the root `Cargo.toml` to the `3.14.0`.

Feel free to decline if it was done on purpose! No worries at all
🙂

Thanks!

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## Test Plan
All units tests are still passing on my side. Let's see with the
pull-request CI 😄

crates/uv-python/Cargo.toml

@@ -74,5 +74,5 @@ assert_fs = { version = "1.1.2" }
 indoc = { version = "2.0.5" }
 itertools = { version = "0.13.0" }
 temp-env = { version = "0.3.6" }
-tempfile = { version = "3.12.0" }
+tempfile = { workspace = true }
 test-log = { version = "0.2.16", features = ["trace"], default-features = false }