Use chipflow fork of amaranth-soc as need the unmerged docs changes

Author: robtaylor

pyproject.toml

@@ -16,7 +16,7 @@ license = {file = "LICENSE.md"}
 requires-python = ">=3.10"
 dependencies = [
     "amaranth[builtin-yosys]>=0.5,<0.7",
-    "amaranth-soc @ git+https://github.com/amaranth-lang/amaranth-soc",
+    "amaranth-soc @ git+https://github.com/ChipFlow/amaranth-soc",
     "amaranth-boards @ git+https://github.com/amaranth-lang/amaranth-boards",
     "yowasp-nextpnr-ecp5>=0.7",
     "yowasp-runtime",