Drop patch that was applied upstream

debian/patches/series

@@ -1,2 +1 @@
-tests-Unset-SOURCE_DATE_EPOCH.patch
 debian/Skip-test-pull-repeated-during-CI.patch

debian/patches/tests-Unset-SOURCE_DATE_EPOCH.patch

@@ -1,34 +0,0 @@
-From: Simon McVittie <smcv@collabora.com>
-Date: Mon, 26 Jul 2021 11:48:45 +0100
-Subject: tests: Unset SOURCE_DATE_EPOCH
-
-Some distributions set this during build in order to have reproducible
-builds from the same source code: for example, Debian uses the date
-from debian/changelog.
-
-However, some of our tests assume that `ostree commit` will result in
-a commit with the current date/time, and SOURCE_DATE_EPOCH breaks that
-assumption. Unset it for our build-time tests.
-
-Bug: https://github.com/ostreedev/ostree/issues/2405
-Signed-off-by: Simon McVittie <smcv@collabora.com>
-Applied-upstream: 2021.4, commit:2c5fa2cdb6c304394ca629c959ec53d878f3f93a
----
- tests/libtest.sh | 4 ++++
- 1 file changed, 4 insertions(+)
-
-diff --git a/tests/libtest.sh b/tests/libtest.sh
-index 260b8d1..f04ccaa 100755
---- a/tests/libtest.sh
-+++ b/tests/libtest.sh
-@@ -69,6 +69,10 @@ if ! test -f .testtmp; then
-     touch .testtmp
- fi
- 
-+# Some distribution builds set this, but some of our build-time tests
-+# assume this won't be used when committing
-+unset SOURCE_DATE_EPOCH
-+
- # Also, unbreak `tar` inside `make check`...Automake will inject
- # TAR_OPTIONS: --owner=0 --group=0 --numeric-owner presumably so that
- # tarballs are predictable, except we don't want this in our tests.