fix: uBlue OS should be detected as FedoraImmutable (#1043)

* refactor(parse_os_release): Don't rely on specific `ID`s for Fedora Immutable

Instead match `ID=fedora` or `ID_LIKE=fedora` and decide wether or not
the distro is immutable by `VARIANT`.

* feat: add aurora,bluefin,coreos support

The `os_release`s came from the following images:

- ghcr.io/ublue-os/aurora:93f0fd9f20b3
- ghcr.io/ublue-os/bluefin:5d37394a5d4b
- ghcr.io/ublue-os/ucore:63cd1200c344

* fix: bazzite should be detected as FedoraImmutable

* squash me: cargo fmt

---------

Co-authored-by: Steve Lau <stevelauc@outlook.com>

src/steps/os/os_release/bluefin

@@ -0,0 +1,24 @@
+NAME="Bluefin"
+VERSION="41.20250216.1 (Silverblue)"
+RELEASE_TYPE=stable
+ID=bluefin
+ID_LIKE="fedora"
+VERSION_ID=41
+VERSION_CODENAME="Archaeopteryx"
+PLATFORM_ID="platform:f41"
+PRETTY_NAME="Bluefin (Version: 41.20250216.1 / FROM Fedora Silverblue 41)"
+ANSI_COLOR="0;38;2;60;110;180"
+LOGO=fedora-logo-icon
+CPE_NAME="cpe:/o:universal-blue:bluefin:41"
+DEFAULT_HOSTNAME="bluefin"
+HOME_URL="https://projectbluefin.io"
+DOCUMENTATION_URL="https://docs.projectbluefin.io"
+SUPPORT_URL="https://github.com/ublue-os/bluefin/issues/"
+BUG_REPORT_URL="https://github.com/ublue-os/bluefin/issues/"
+SUPPORT_END=2025-12-15
+VARIANT="Silverblue"
+VARIANT_ID=bluefin
+OSTREE_VERSION='41.20250216.1'
+BUILD_ID="185146a"
+IMAGE_ID="bluefin"
+IMAGE_VERSION="41.20250216.1"