Fix systemd service example

[mysubb01]

Summary

• update the systemd ExecStart example so JVM options are passed before the module path/main module
• replace UseParallelOldGC with UseParallelGC and set -Dcontainerized=false for the non-containerized service example
• create ~/bin and ~/var/lib/questdb in the setup snippet so first-time installs have the required paths
• fix a few small wording typos on the page

Verification

• source /Users/wy/.nvm/nvm.sh && nvm exec 22.22.2 npx --yes yarn@1.22.22 install --frozen-lockfile
• source /Users/wy/.nvm/nvm.sh && nvm exec 22.22.2 npx --yes yarn@1.22.22 build
• git diff --check

Fixes questdb/questdb#4265
Related to #224 and questdb/questdb#4258

[javier]

Thanks!

[github-actions]

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[enricobenedos]

Thanks @mysubb01,

but unfortunately the Java installation steps are wrong. In fact the Oracle JDK download link doesn't work. Should the JDK the right choice or maybe JRE is enough?

At this point a good idea should be to use AdoptOpenJDK or other sources? For example Debian is shipped with a default JRE.

[javier]

Thanks @enricobenedos. It seems the link is stale now. In any case, I also updated to use OpenJDK, as it is the one we use for CI. And also bumped the version, since we recently moved to support java 25 #461