Revert "Fix issue with "$$" in Script blocks"

[ghost]

Changes

Fixes #3935

This reverts commit 9a9f896.

Attempting to fix instances of "$$" introduced a new bug in the way
bash scripts are interpreted: #3935

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Release Notes

Revert fix for instances of "$$" in script blocks. Kubernetes replaces "$$" with a single "$" and your scripts need to deal appropriately with these instances.

[ghost]

/kind misc

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[jerop]

/lgtm