component/libgit3: prefer python3 for build tests

component/libgit2/buildout.cfg

@@ -17,6 +17,7 @@ md5sum = 9f4ca15249e703ab88cbc929187750cd
 version = 1.1.0
 shared = true
 configure-command =
+  sed -i '1s/^/set(Python_ADDITIONAL_VERSIONS 3 2.7)\n /' tests/CMakeLists.txt &&
   cmake
 configure-options =
   -Bbuild
@@ -29,5 +30,5 @@ configure-options =
 make-options = -C build
 environment =
   PKG_CONFIG_PATH=${openssl:location}/lib/pkgconfig:${zlib:location}/lib/pkgconfig:${xz-utils:location}/lib/pkgconfig
-  PATH=${python:location}/bin:${pkgconfig:location}/bin:${cmake:location}/bin:%(PATH)s
+  PATH=${python3:location}/bin:${pkgconfig:location}/bin:${cmake:location}/bin:%(PATH)s
   LDFLAGS=-L${openssl-1.0:location}/lib -Wl,-rpath=${openssl:location}/lib -L${pcre:location}/lib -Wl,-rpath=${pcre:location}/lib