[Config] Add Use Path as Transaction Name and Add Transaction Name Groups

[jackshirazi]

Classic agent link

• https://www.elastic.co/guide/en/apm/agent/java/current/config-http.html#config-use-path-as-transaction-name
• https://www.elastic.co/guide/en/apm/agent/java/current/config-core.html#config-transaction-name-groups

What it does

Use Path as Transaction Name makes transaction names of unsupported or partially-supported frameworks be in the form of $method $path instead of just $method.
Add Transaction Name Groups groups transaction names that contain dynamic parts, using a wildcard expression. For example, the pattern GET /user/*/cart would consolidate transactions, such as GET /users/42/cart and GET /users/73/cart into a single transaction name GET /users/*/cart

Implementation difficulty, location, and dynamism

• I think this is easiest done in the exporter - look for http spans with just "$method" as name, and add a (partial) path if available; and do wildcard matching and change the name for the groups. The support for queue transaction names can be done too, but if any difficulty (eg identifying queue spans), then drop or shift to phase 2. Alternatively, we could make this generic and apply to ALL spans
• It can be contributed upstream
• It can be dynamic