Clone results in "remote HEAD refers to nonexistent ref"

Running the following command:

$ git clone git@ConnectorHost:gD1/repo8

results in:

Cloning into 'repo8'...
remote: Counting objects: 3, done.
remote: Total 3 (delta 0), reused 0 (delta 0)
Receiving objects: 100% (3/3), done.
Checking connectivity... done.
warning: remote HEAD refers to nonexistent ref, unable to checkout.

To resolve this issue, do one of the following:

Edit the repo spec to specify refs/heads/main as the default branch to clone from. This is required for any repo not using the refs/heads/master default branch. For details, see Specify a default branch.
Run the following special command to set the default branch to refs/heads/main:
```
$ git clone git@ConnectorHost:@defaultbranch:gD1/repo8=refs/heads/main
```
This results in the following output:
```
git clone git@ConnectorHost:@defaultbranch:gD1/repo8=refs/heads/main
Cloning into 'repo8=refs/heads/main'...
repo='gD1/repo8', old DefaultBranch='', new DefaultBranch='refs/heads/main'
fatal: Could not read from remote repository.
```
Note
The special command sets the default branch even if Git cannot parse it and the commands terminates with:
```
Fatal: Could not read from remote repository.
```
You can also run @defaultbranch:gD1/repo8 to show the default branch and @defaultbranch:gD1/repo8= to clear the default branch.