gnu: python-scm-sr-ht: Remove set-version phase.

* gnu/packages/sourcehut.scm (python-scm-sr-ht):
[phases]{set-version}: Remove phase.
[native-inputs]: Add python-setuptools-scm.

Change-Id: I2b1ac766fcace10bf463371f255e589f464b1567

gnu/packages/sourcehut.scm

@@ -94,14 +94,12 @@
     (build-system pyproject-build-system)
     (arguments
      (list
-      #:tests? #false                   ;there are none
-      #:phases
-      #~(modify-phases %standard-phases
-          (add-after 'unpack 'set-version
-            (lambda _ (setenv "PKGVER" #$version))))))
+      #:tests? #false))                   ;there are none
     (propagated-inputs
      (list python-core-sr-ht))
-    (native-inputs (list python-setuptools))
+    (native-inputs
+     (list python-setuptools
+           python-setuptools-scm))
     (home-page "https://git.sr.ht/~sircmpwn/scm.sr.ht")
     (synopsis "Shared support code for sr.ht source control services")
     (description