ci: extract RPC version from protected gitlab-ci.yml

Description

ci: extract RPC version from protected gitlab-ci.yml

RPC version variable must be updated before each release. Currently, this requires modification of gitlab-ci.yml, which requires approval from the code owner. To simplify the release process for developers, variable will be extracted to a separate file, whose change will not require an approval.

How to test

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Author's checklist

• I have followed the contribution guidelines
• [-] This MR has been tested or does not change functionality
• I have added relevant merge request dependencies (if this MR has any)
• I have added the correct labels
• I have assigned reviewers (if any are relevant)
• [-] I have edited the documentation (if the changes require it) or I have noted the need for the change if I do not have access to the documentation
• I have marked all introduced BREAKING CHANGES or necessary DEPLOYMENT NOTES in the commit message(s)

Reviewer's checklist

• This MR has been tested or does not change functionality
• This MR has correct commit message format

Other information

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Related issues

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