requirements: update fastkde requirement

Updates the requirements on [fastkde](https://github.com/LBL-EESA/fastkde) to permit the latest version.
- [Release notes](https://github.com/LBL-EESA/fastkde/releases)
- [Commits](LBL-EESA/fastkde@v1.0.24...v1.0.26)

---
updated-dependencies:
- dependency-name: fastkde
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

requirements.txt

@@ -1,7 +1,7 @@
 autograd<1.7
 beartype<0.15.0
 dill<0.3.7
-fastkde>=1.0.24, <1.0.25
+fastkde>=1.0.24, <1.0.27
 graph-scheduler>=0.2.0, <1.1.3
 graphviz<0.21.0
 grpcio<1.57.0