Don't assume UTC+0 time zone

--- a/rage/tests/cmd/rage-keygen/gen-output.out/key.txt
+++ b/rage/tests/cmd/rage-keygen/gen-output.out/key.txt
@@ -1,3 +1,3 @@
-# created: 20[..]-[..]-[..]T[..]:[..]:[..]Z
+# created: 20[..]-[..]-[..]T[..]:[..]:[..]
 # public key: age1[..]
-AGE-SECRET-KEY-1[..]
\ No newline at end of file
+AGE-SECRET-KEY-1[..]
--- a/rage/tests/cmd/rage-keygen/gen-stdout.toml
+++ b/rage/tests/cmd/rage-keygen/gen-stdout.toml
@@ -1,7 +1,7 @@
 bin.name = "rage-keygen"
 args = ""
 stdout = """
-# created: 20[..]-[..]-[..]T[..]:[..]:[..]Z
+# created: 20[..]-[..]-[..]T[..]:[..]:[..]
 # public key: age1[..]
 AGE-SECRET-KEY-1[..]
 """