ci: use make rc to release candidate without tag

[zimeg]

Changelog

Nothing but an oopsies in prior change...

Summary

This PR follows #552 to use the correct make target.

Preview

🔗 https://github.com/slackapi/slack-cli/actions/runs/26257441914/job/77283314836

Testing

slack-cli/Makefile

Lines 76 to 79 in dd404fe

	# Create a release candidate commit with updated docs
	# Usage: `make rc RELEASE_VERSION=3.7.0-example`
	.PHONY: rc
	rc:

Requirements

• I've read and understood the Contributing Guidelines and have done my best effort to follow them.
• I've read and agree to the Code of Conduct.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 71.67%. Comparing base (dd404fe) to head (b8a732c).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #557   +/-   ##
=======================================
  Coverage   71.67%   71.67%           
=======================================
  Files         226      226           
  Lines       19115    19115           
=======================================
  Hits        13701    13701           
- Misses       4208     4209    +1     
+ Partials     1206     1205    -1     

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[zimeg]

🗣️ I am nervous of a broken main so fast merge now!