Docs regarding engine_version

[socketbox]

The README states:

When engine is redis and the version is 6 or higher, the major and minor version can be set, e.g., 6.2, or the minor version can be unspecified which will use the latest version at creation time, e.g., 6.x.

However, when I use both "7" and "7.x" to specify a series 7 version, TF returns an error:

╷
│ Error: engine_version: 7.x is invalid. For Redis v6 or higher, use <major>.<minor>. For Redis v5 or lower, use <major>.<minor>.<patch>.
│ 
│   with module.lite.module.pbsorg.module.redis.aws_elasticache_replication_group.replication_group,
│   on .terraform/modules/lite.pbsorg.redis/main.tf line 12, in resource "aws_elasticache_replication_group" "replication_group":
│   12:   engine_version              = var.engine_version

In consulting the docs, I cannot find an option that allows one to specify a major version and have AWS choose the latest minor version in that series. For example, passing in redis7 would return a list of two versions, 7.0 and 7.1.