Ensure sqlez build succeeds on Windows (#7072)

On Windows, `OsStr` must be a valid
[WTF-8](https://simonsapin.github.io/wtf-8/) sequence, and there are no
safety ways converting from bytes to OsStr in std. So I added
`PathExt::try_from_bytes` and use it in `sqlez`.

crates/util/Cargo.toml

@@ -31,6 +31,9 @@ git2 = { workspace = true, optional = true }
 dirs = "3.0"
 take-until = "0.2.0"
 
+[target.'cfg(windows)'.dependencies]
+tendril = "0.4.3"
+
 [dev-dependencies]
 tempfile.workspace = true
 git2.workspace = true