I am using the yum module to lock the release version for a RHEL 7.6 machine to 7.7 version. However the yum --releasever option does not set the release version to 7.7. I am using Ansible 2.7.10 version.
Here is the discussion regarding the issue: 
https://access.redhat.com/discussions/4774501

ISSUE TYPE
Bug Report

COMPONENT NAME
yum --releasever

ANSIBLE VERSION
2.7.10 

STEPS TO REPRODUCE
name: installing updated packages
yum:
name: '*'
state: latest
releasever: '7.7'

ACTUAL RESULTS
Play runs successfully however it does not update the release version of the server
global rpmbin
            if not rpmbin:
                rpmbin = self.module.get_bin_path('rpm', required=True)
            cmd = [rpmbin, '-q', '--qf', qf, pkgspec]
            if self.installroot != '/':
                cmd.extend(['--root', self.installroot])
            
            
            lang_env = dict(LANG='C', LC_ALL='C', LC_MESSAGES='C')
            rc, out, err = self.module.run_command(cmd, environ_update=lang_env)
            if rc != 0 and 'is not installed' not in out:
                self.module.fail_json(msg='Error from rpm: %s: %s' % (cmd, err))
            if 'is not installed' in out:
                out = ''
            pkgs = [p for p in out.replace('(none)', '0').split('\n') if p.strip()]
            if not pkgs and not is_pkg:
                cmd = [rpmbin, '-q', '--qf', qf, '--whatprovides', pkgspec]
                if self.installroot != '/':
                    cmd.extend(['--root', self.installroot])
                rc2, out2, err2 = self.module.run_command(cmd, environ_update=lang_env)
            else:
                rc2, out2, err2 = (0, '', '')
            if rc2 != 0 and 'no package provides' not in out2:
                self.module.fail_json(msg='Error from rpm: %s: %s' % (cmd, err + err2))
            if 'no package provides' in out2:
                out2 = ''
            pkgs += [p for p in out2.replace('(none)', '0').split('\n') if p.strip()]
            return pkgs
        return []
    def is_available(self, repoq, pkgspec, qf=def_qf):