JENKINS-24728 broke our use of shallow clone. Basically, we are getting the following error:

```
> git config remote.origin.url git@REDACTED # timeout=10
Pruning obsolete local branches
Fetching upstream changes from git@REDACTED
> git --version # timeout=10
using GIT_SSH to set credentials
> git -c core.askpass=true fetch --tags --progress git@REDACTED +refs/heads/:refs/remotes/origin/ --prune --depth=1
Checking out Revision 1f2bf20dfc5a408d56181c9db99ac994545f44c3 (origin/master)
> git config core.sparsecheckout # timeout=10
> git checkout -f 1f2bf20dfc5a408d56181c9db99ac994545f44c3 # timeout=10
FATAL: Could not checkout master with start point 1f2bf20dfc5a408d56181c9db99ac994545f44c3
hudson.plugins.git.GitException: Could not checkout master with start point 1f2bf20dfc5a408d56181c9db99ac994545f44c3
at org.jenkinsci.plugins.gitclient.CliGitAPIImpl$9.execute(CliGitAPIImpl.java:1990)
at org.jenkinsci.plugins.gitclient.RemoteGitImpl$CommandInvocationHandler$1.call(RemoteGitImpl.java:152)
at org.jenkinsci.plugins.gitclient.RemoteGitImpl$CommandInvocationHandler$1.call(RemoteGitImpl.java:145)
at hudson.remoting.UserRequest.perform(UserRequest.java:121)
at hudson.remoting.UserRequest.perform(UserRequest.java:49)
at hudson.remoting.Request$2.run(Request.java:324)
at hudson.remoting.InterceptingExecutorService$1.call(InterceptingExecutorService.java:68)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at hudson.remoting.Engine$1$1.run(Engine.java:63)
at java.lang.Thread.run(Thread.java:745)
at ......remote call to i-b8caab51-5500c494(Native Method)
at hudson.remoting.Channel.attachCallSiteStackTrace(Channel.java:1416)
at hudson.remoting.UserResponse.retrieve(UserRequest.java:220)
at hudson.remoting.Channel.call(Channel.java:781)
at org.jenkinsci.plugins.gitclient.RemoteGitImpl$CommandInvocationHandler.execute(RemoteGitImpl.java:145)
at sun.reflect.GeneratedMethodAccessor705.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.jenkinsci.plugins.gitclient.RemoteGitImpl$CommandInvocationHandler.invoke(RemoteGitImpl.java:131)
at com.sun.proxy.$Proxy72.execute(Unknown Source)
at hudson.plugins.git.GitSCM.checkout(GitSCM.java:1135)
at hudson.scm.SCM.checkout(SCM.java:485)
at hudson.model.AbstractProject.checkout(AbstractProject.java:1269)
at hudson.model.AbstractBuild$AbstractBuildExecution.defaultCheckout(AbstractBuild.java:607)
at jenkins.scm.SCMCheckoutStrategy.checkout(SCMCheckoutStrategy.java:86)
at hudson.model.AbstractBuild$AbstractBuildExecution.run(AbstractBuild.java:529)
at hudson.model.Run.execute(Run.java:1738)
at hudson.matrix.MatrixRun.run(MatrixRun.java:146)
at hudson.model.ResourceController.execute(ResourceController.java:98)
at hudson.model.Executor.run(Executor.java:410)
Caused by: hudson.plugins.git.GitException: Command "git checkout -f 1f2bf20dfc5a408d56181c9db99ac994545f44c3" returned status code 128:
stdout:
stderr: fatal: reference is not a tree: 1f2bf20dfc5a408d56181c9db99ac994545f44c3

at org.jenkinsci.plugins.gitclient.CliGitAPIImpl.launchCommandIn(CliGitAPIImpl.java:1719)
at org.jenkinsci.plugins.gitclient.CliGitAPIImpl.launchCommandIn(CliGitAPIImpl.java:1695)
at org.jenkinsci.plugins.gitclient.CliGitAPIImpl.launchCommandIn(CliGitAPIImpl.java:1691)
at org.jenkinsci.plugins.gitclient.CliGitAPIImpl.launchCommand(CliGitAPIImpl.java:1321)
at org.jenkinsci.plugins.gitclient.CliGitAPIImpl.launchCommand(CliGitAPIImpl.java:1333)
at org.jenkinsci.plugins.gitclient.CliGitAPIImpl$9.execute(CliGitAPIImpl.java:1966)
at org.jenkinsci.plugins.gitclient.RemoteGitImpl$CommandInvocationHandler$1.call(RemoteGitImpl.java:152)
at org.jenkinsci.plugins.gitclient.RemoteGitImpl$CommandInvocationHandler$1.call(RemoteGitImpl.java:145)
at hudson.remoting.UserRequest.perform(UserRequest.java:121)
at hudson.remoting.UserRequest.perform(UserRequest.java:49)
at hudson.remoting.Request$2.run(Request.java:324)
at hudson.remoting.InterceptingExecutorService$1.call(InterceptingExecutorService.java:68)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at hudson.remoting.Engine$1$1.run(Engine.java:63)
at java.lang.Thread.run(Thread.java:745)
```

From comparing build logs, I believe that the issue is this line:

```
git -c core.askpass=true fetch --tags --progress git@REDACTED +refs/heads/:refs/remotes/origin/ --prune --depth=1
```

From a build with a prior version of the plugin, I see the following output:

```
git -c core.askpass=true fetch --tags --progress git@git.freelancer.com:eng/production.git +refs/heads/:refs/remotes/origin/ --prune
```