Hi @Anonymous,
I think there is something issue with the Uri that you specified within the Uri field of the "Send an HTTP request to SharePoint" action.
In addition, the text() function is not supported in expressions of Microsoft Flow currently. More details about the expressions supported in Microsoft Flow currently, please check the following article:
https://docs.microsoft.com/en-us/azure/logic-apps/workflow-definition-language-functions-reference
I have made a test on my side and please take a try with the following workaround:
The flow works successfully as below:
If you could not find the ID dynamic content of the trigger, please consider take a try to click "See more" button within the "When an item is created or modified" trigger section of right Dynamic content tab, then check if the ID dynamic content has been shown up:
In addition, you could also type the following formula within the Uri field of the "Send an HTTP request to SharePoint" action:
_api/web/lists(guid'7adab573-9d27-4129-abc0-faca0ae45fe8')/items(@{triggerBody()?['ID']})/versions

Best regards,
Kris