Improve time required to clone repositories in initContainer

[ZohebShaikh]

Currently the repos are cloned in sync and it clones everything(default)

The solution that I propose to this is

1. Using Asycn IO to do the clone ( There is no native support for this but it is easy to implement more details here)

2. Do git clone with the following option --filter=blob:none more details here

There is --filter=tree:0 which is also a good option but in my personal opinion going with blob:none is better because the thing that we want to avoid cloning is the gh-pages branch but clone most of the source code which the blob:none is good at.

Here is the size difference for the following options for blueapi in terms of size

311M    /tmp/blueapi/
11M     /tmp/blueapi-blob-none/ # --filter=blob:none
6.9M    /tmp/blueapi-tree-0/ # --filter=tree:0

And for dodal much bigger improvement

585M    /tmp/dodal/
33M     /tmp/dodal-blob-none/ #--filter=blob:none
9.8M    /tmp/dodal-tree-0/ # --filter=tree:0

To clone dodal without any options takes 1m35s

This is a better approach and will definetly improve the time required for the initContainer to start

Acceptance Criteria

• InitContainer start time with large git repositories significantly faster than before

[ZohebShaikh]

Even if the old docs are removed #1345 , This should still give some performance improvement