Move symlink generation into the base Dockerfile

[Justin-Walsh]

Team

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What happened?

We symlink Tentacle into /usr/local/bin in the configure tentacle script, which runs at container start. For users running the container in a readonlyrootfilesystem security context, this means that they need to use a volume mount or other convoluted setup for this one file.

Reproduction

• Run the Tentacle in a readonlyrootfilesystem (with /home/tentacle and /etc/octopus as volume mounts
• Start container
• 💥

Error and Stacktrace

`ln: failed to create symbolic link '/usr/bin/tentacle': Read-only file system`

More Information

No response

Workaround

No response

[LukeButters]

Release Note: Tentacle docker container now Supports readonlyrootfilesystem #850