What to do when PhD approval takes so long?
While the details of the assessment/examination process vary around the world, everywhere (that I'm aware of) has the same issue that there is a time lag between handing in your thesis and receiving a decision. That time lag is a few weeks as a minimum, often several months.

This does not generally cause major issues with job applications. Employers who are accustomed to hiring postdoctoral researchers will be very familiar with the delay, and are generally happy to offer a job and have you start working (and being paid) pending the award of the PhD. It will be clear to them, from the reference/recommendation letter from your advisor, whether or not you are likely to pass the PhD. If there is a chance that you might fail completely, it's unlikely that you would even be applying for postdoc jobs, let alone being offered them. I think that technically the employer would have the option of reconsidering your contract were you to unexpectedly fail the PhD, but I have never heard of that actually occurring in practice.