gnu: python-project-metadata-0.7: Remove.

As it's redundant as of 1039ec03be.

* gnu/packages/python-xyz.scm (python-pyproject-metadata-0.7): Remove
variable.
* gnu/packages/build-tools.scm (meson-python): Use python-pyproject-metadata
rather than python-pyproject-metadata-0.7.

Change-Id: I50d458ff636cfab3a262e7d0759e88f14f68081f

gnu/packages/build-tools.scm

@@ -374,7 +374,7 @@ resembles Python.")
            ninja
            python-colorama
            python-cython
-           python-pyproject-metadata-0.7
+           python-pyproject-metadata
            python-tomli
            python-typing-extensions
            python-wheel))

gnu/packages/python-xyz.scm

@@ -14306,22 +14306,6 @@ validate this input and generate a PEP 643-compliant metadata
 file (e.g. @file{PKG-INFO}).")
     (license license:expat)))
 
-(define-public python-pyproject-metadata-0.7
-  (package
-    (inherit python-pyproject-metadata)
-    (name "python-pyproject-metadata")
-    (version "0.7.1")
-    (source
-     (origin
-       (method git-fetch)
-       (uri (git-reference
-             (url "https://github.com/FFY00/python-pyproject-metadata")
-             (commit version)))
-       (file-name (git-file-name name version))
-       (sha256
-        (base32
-         "0yvs59ymz5gdix34a95wxlxvk9bnvjgrzsnmnc3ws7whpfv3yasm"))))))
-
 ;; pep621 was renamed to pyproject-metadata.
 (define-public python-pep621
   (deprecated-package "python-pep621" python-pyproject-metadata))