Add storetype option to keytool command example for linux

[solsticedhiver]

Also specify storetype of JKS for linux example

Description of what this PR is changing or adding, and why:
Correct the linux keytool example and add -storetype JKS to match the windows example

Issues fixed by this PR (if any):

PRs or commits this PR depends on (if any):

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[gemini-code-assist]

Code Review

This pull request correctly adds the -storetype JKS option to the keytool command example for Linux/macOS, aligning it with the Windows example and ensuring it works correctly with modern Java versions. I have one suggestion to improve the formatting of the command for better readability and consistency.

[sfshaza2]

@solsticedhiver, can you address the bot's feedback?