Actor type in sequence diagram has wrong ordering

[emmachase]

Description

When using the actor participant type, z-ordering is incorrect, showing the line above other elements like notes.

Steps to reproduce

1. Create a sequence diagram that uses an actor
2. Add a note over the actor
3. Observe that the note's box and text are ordered underneath the actor line/lifetime

https://develop.git.mermaid.live/edit#pako:eNpdkD0OwjAMha9ieWEpF4hEJX4GmFmzmMS0EUlc0hQJIe5OKEVUeHLee5-d5IFGLKPCnq8DR8M7R02ioCOUIpMlwdo7w3NhI6fPsaOUnXEdxQzblpJ3U25ElnVdkgr27keUpsijPRqz2VEyg9x4WljBCK--BdKWCPc_5R-bbqDgsAhA3kMjYrHCwCmQs-WRjzeiMbccWKMqraV00ajjs-RoyHK8R4Mqp4ErHDpL-fshqM7ke36-AL2pYU4

Screenshots

Code Sample

sequenceDiagram
    actor Alice
    actor Bob
    participant Charlie
    Alice->>Bob: Hi Bob
    Bob->>Alice: Hi Alice
    note over Alice, Bob: ========= oh noes =========
    note over Charlie: I'm all good

Setup

• Mermaid version: v11.0.0-alpha.7+7bcba29
• Browser and Version: Reproduced in Chrome and Firefox, haven't tested any other browsers, likely not browser dependent.

Suggested Solutions

I'm not super familiar with how the svg code works, but from an initial glace it seems suspicious that this line calls lower directly on elem

mermaid/packages/mermaid/src/diagrams/sequence/svgDraw.js

Line 418 in 7bcba29

elem.lower();

This is opposed to how it works in the participant function, in which a g is created first to contain the elements:

mermaid/packages/mermaid/src/diagrams/sequence/svgDraw.js

Line 333 in 7bcba29

const boxplusLineGroup = elem.append('g').lower();

Additional Context

No response