[Glossary] The definition of "session" is not complete

[scottsun94]

Description

Here is the current definition: https://docs.ray.io/en/latest/ray-references/glossary.html?highlight=session#term-Session

However, the /tm/ray/session_*/ structure indicates that a new session is created whenever a new ray cluster/runtime is started. People will find them in places like https://docs.ray.io/en/latest/ray-observability/ray-logging.html#logging-directory-structure

Link

https://docs.ray.io/en/latest/ray-references/glossary.html?highlight=session#term-Session

[scottsun94]

We should be able to fix this kind of small issue in the next release like 2.5?