Small fix, rewrite the Package builds section

This MR:

• removes the use of snapshotted
• rewrites the Package builds section adding more details about package builds using the SDK, devroots and snapshots of APT archives. It mentions the differences between building on OBS and on the SDK and differences between native and emulated builds.

content/architecture/long-term-reproducibility.md

@@ -311,8 +311,8 @@ the remaining planned improvements.
 Apertis uses [OBS](https://openbuildservice.org/) for building packages,
 however since the purpose of the long term reproducibility does not involve
 large scale package rebuilds, we recommend using the [Apertis
-SDK](designs/software-development-kit/) for building packages. In addition to
-the SDK a [devroot](architecture/sysroots-and-devroots/#devroot) and a snapshot
+SDK]({{< ref "software-development-kit.md" >}}) for building packages. In addition to
+the SDK a [devroot]({{< ref "sysroots-and-devroots/#devroot" >}}) and a snapshot
 of the APT repositories are also required.
 
 We recommend the SDK release to match the release of Apertis in the target
@@ -321,7 +321,7 @@ devroot and of the snapshot of the APT repositories matches the target device.
 As an example, if the target is an `ARM64` device, the devroot and the snapshot
 of the APT repositories should also be for `ARM64`.
 
-See the [devroot](architecture/sysroots-and-devroots/#devroot) for more
+See the [devroot]({{< ref "sysroots-and-devroots/#devroot" >}}) for more
 information.
 
 For the long term reproducibility we recommend the product team to have a
@@ -337,7 +337,7 @@ changes to the packages being build using emulation, and they may produce
 different results when compared to native builds.
 
 For more information about emulated and native builds see
-[Build infrastructure on Intel x86-64](designs/x86-build-infrastructure/).
+[Build infrastructure on Intel x86-64]({{< ref "x86-build-infrastructure.md" >}}).
 
 Building packages on the SDK uses emulation, and while this approach is
 currently expected to be satisfactory, it may produce different results when