Fedora builds are reproducible, but for the date in the tar file?

[rustyrussell]

Should probably use the same flow as the Ubuntu builds, and create a .xz, but either way, it needs to use --mtime to tar:

--- /home/rusty/Downloads/clightning-v25.09.1-Fedora-35-amd64.tar.gz
+++ release/clightning-v25.09.1-Fedora-35-amd64.tar.gz
├── filetype from file(1)
│ @@ -1 +1 @@
│ -gzip compressed data, from Unix, original size modulo 2^32 149626880 gzip compressed data, reserved method, ASCII, has CRC, extra field, has comment, from FAT filesystem (MS-DOS, OS/2, NT)
│ +gzip compressed data, from Unix, original size modulo 2^32 149626880 gzip compressed data, reserved method, ASCII, extra field, encrypted, from FAT filesystem (MS-DOS, OS/2, NT)
├── clightning-v25.09.1-Fedora-35-amd64.tar
│ ├── file list
│ │ @@ -1,200 +1,200 @@
│ │ -drwxr-xr-x   0 root         (0) root         (0)        0 2025-10-15 00:58:50.000000 usr/
│ │ -drwxr-xr-x   0 root         (0) root         (0)        0 2025-10-15 00:58:50.000000 usr/local/
│ │ -drwxr-xr-x   0 root         (0) root         (0)        0 2025-10-15 00:58:50.000000 usr/local/bin/
│ │ --rwxr-xr-x   0 root         (0) root         (0)   332808 2025-10-15 00:58:50.000000 usr/local/bin/lightning-cli
│ │ --rwxr-xr-x   0 root         (0) root         (0)  3593760 2025-10-15 00:58:50.000000 usr/local/bin/lightning-hsmtool
│ │ --rwxr-xr-x   0 root         (0) root         (0)    83126 2025-10-15 00:58:50.000000 usr/local/bin/reckless
...
│ │ +drwxr-xr-x   0 root         (0) root         (0)        0 2025-10-15 23:24:22.000000 usr/
│ │ +drwxr-xr-x   0 root         (0) root         (0)        0 2025-10-15 23:24:22.000000 usr/local/
│ │ +drwxr-xr-x   0 root         (0) root         (0)        0 2025-10-15 23:24:22.000000 usr/local/share/
│ │ +drwxr-xr-x   0 root         (0) root         (0)        0 2025-10-15 23:24:22.000000 usr/local/share/man/
│ │ +drwxr-xr-x   0 root         (0) root         (0)        0 2025-10-15 23:24:22.000000 usr/local/share/man/man8/
│ │ +-rw-r--r--   0 root         (0) root         (0)     5730 2025-10-15 23:24:22.000000 usr/local/share/man/man8/lightning-hsmtool.8
│ │ +-rw-r--r--   0 root         (0) root         (0)     7422 2025-10-15 23:24:22.000000 usr/local/share/man/man8/lightningd.8
│ │ +drwxr-xr-x   0 root         (0) root         (0)        0 2025-10-15 23:24:22.000000 usr/local/share/man/man1/
│ │ +-rw-r--r--   0 root         (0) root         (0)     6014 2025-10-15 23:24:22.000000 usr/local/share/man/man1/lightning-reckless.1