Update debootstrap to enable riscv64 support

[am11]

Merge Checklist

All boxes should be checked before merging the PR (just tick any boxes which don't apply to this PR)

• [x] The toolchain has been rebuilt successfully (or no changes were made to it)
• [x] The toolchain/worker package manifests are up-to-date
• [x] Any updated packages successfully build (or no packages were changed)
• [x] All package sources are available
• [x] cgmanifest files are up-to-date and sorted (./cgmanifest.json, ./toolkit/scripts/toolchain/cgmanifest.json, .github/workflows/cgmanifest.json)
• [x] Documentation has been updated to match any changes to the build system
• [x] Ready to merge

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Summary

This PR upgrades debootstrap to latest release to help .NET Runtime project build their riscv64 cross toolchain.

Change Log

• Upgrade to version 1.0.134 to support RISC-V architecture

Does this affect the toolchain?

NO

Associated issues

• #9418