Update PseudoPotentialData requirement from 0.2 to 0.2, 0.3 in /docs

Updates the requirements on [PseudoPotentialData](https://github.com/JuliaMolSim/PseudoPotentialData.jl) to permit the latest version.
- [Release notes](https://github.com/JuliaMolSim/PseudoPotentialData.jl/releases)
- [Commits](JuliaMolSim/PseudoPotentialData.jl@v0.2.0...v0.3.0)

---
updated-dependencies:
- dependency-name: PseudoPotentialData
  dependency-version: 0.3.0
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

docs/Project.toml

@@ -28,6 +28,6 @@ DFTK = "0.7"
 Documenter = "~1.8, 1.16"
 EmpiricalPotentials = "0.2.5"
 GeometryOptimization = "0.1.5"
-PseudoPotentialData = "0.2"
+PseudoPotentialData = "0.2, 0.3"
 Unitful = "1.28.0"
 UnitfulAtomic = "1.0.0"