Append version to RID only with valid characters

[am11]

This is the init-distro-rid.sh counterpart of 31e4f40.

In amd64/archlinux docker container, the non-portable RID auto-detection (without explicit -p:TargetRid=arch-x64 arg or __DistroRid=arch-x64 env var) looks like this:

Before: __DistroRid: arch.TEMPLATE_VERSION_ID-x64
After: __DistroRid: arch-x64

[dotnet-issue-labeler]

I couldn't figure out the best area label to add to this PR. If you have write-permissions please help me learn by adding exactly one area label.

[ghost]

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Issue Details

---

This is the init-distro-rid.sh counterpart of 31e4f40.

In amd64/archlinux docker container, the non-portable RID auto-detection (without explicit -p:TargetRid=arch-x64 arg or __DistroRid=arch-x64 env var):

Before: __DistroRid: arch.TEMPLATE_VERSION_ID-x64
After: __DistroRid: arch-x64

Author:	am11
Assignees:	-
Labels:	area-Infrastructure, community-contribution
Milestone:	-

[janvorli]

LGTM, thank you!

[tmds]

lgtm.

For completeness, this isn't used to determine the rid during source-build.
That gets passed down as TargetRid from source-build.
The default is determined by calling RuntimeInformation.RuntimeIdentifier. #80901 should affect that.