Bugzilla

I have two `try` runs with some changes:

### 4 chunks across the board
https://treeherder.mozilla.org/#/jobs?repo=try&revision=b20d25df4f5bd52bae7a8183d580c1772e973b4f

Only a small handful of tests were run in this push:
- windows10-64
- windows10-aarch64

windows10-aarch64 has a failure, not sure if this is caused by the chunk resizing.

Overall, this led me to believe I could further reduce the chunks for faster, more stable platforms (eg. windows10-64, linux64)

### 3 chunks across the board

All platforms were run, and some failures were noted.

It was also noted that `ccov` builds do not like being put into small chunks since their execution time is long.

### Chunk numbers adjusted per platform

Chunks were adjusted as follows:

```
windows10-aarch64/.*: 4
windows7-32/.*: 4
linux64-ccov/debug: 6
macosx64.*/.*: 6
android.*: 6
default: 3
```

I have two `try` runs with some changes:

### 4 chunks across the board
https://treeherder.mozilla.org/#/jobs?repo=try&revision=b20d25df4f5bd52bae7a8183d580c1772e973b4f

Only a small handful of tests were run in this push:
- windows10-64
- windows10-aarch64

windows10-aarch64 has a failure, not sure if this is caused by the chunk resizing.

Overall, this led me to believe I could further reduce the chunks for faster, more stable platforms (eg. windows10-64, linux64)

### 3 chunks across the board

https://treeherder.mozilla.org/#/jobs?repo=try&revision=68f10e20aef5f89bf7598f5165c326e25d06d304

All platforms were run, and some failures were noted.

It was also noted that `ccov` builds do not like being put into small chunks since their execution time is long.

### Chunk numbers adjusted per platform

https://treeherder.mozilla.org/#/jobs?repo=try&revision=da081f84279ecd619f503bcebef59cfeb3495f4a

Chunks were adjusted as follows:

```
windows10-aarch64/.*: 4
windows7-32/.*: 4
linux64-ccov/debug: 6
macosx64.*/.*: 6
android.*: 6
default: 3
```