fix: include lgsm steamcmd dependencies

[MarcStdt]

Summary

• install LGSM-reported missing dependencies in the steamcmd runtime image
• add expect, libxml2-utils/xmllint, and telnet so LGSM start/status helpers do not degrade at runtime

Validation

• docker build -f Dockerfile.steamcmd --build-arg VERSION=v0.1.248 -t druid-steamcmd-deps-test:local .
• docker run --rm --entrypoint sh druid-steamcmd-deps-test:local -lc 'command -v expect && command -v xmllint && command -v telnet'
• git diff --check

[druid-infra]

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