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
lock_timeout:
    description:
      - Amount of time to wait for the yum lockfile to be freed.
    required: false
    default: 30
    type: int
    version_added: "2.8"
  install_weak_deps:
    description:
      - Will also install all packages linked by a weak dependency relation.
      - "NOTE: This feature requires yum >= 4 (RHEL/CentOS 8+)"
    type: bool
    default: "yes"
    version_added: "2.8"
  download_dir:
    description:
      - Specifies an alternate directory to store packages.
      - Has an effect only if I(download_only) is specified.
    type: str
    version_added: "2.8"
notes:
  - When used with a `loop:` each package will be processed individually,
    it is much more efficient to pass the list directly to the `name` option.
  - In versions prior to 1.9.2 this module installed and removed each package
    given to the yum module separately. This caused problems when packages
    specified by filename or url had to be installed or removed together. In
    1.9.2 this was fixed so that packages are installed in one yum
    transaction. However, if one of the packages adds a new yum repository
    that the other packages come from (such as epel-release) then that package
    needs to be installed in a separate task. This mimics yum's command line