Patch to fix spelling errors
### Description
The lintian QA tool reported a spelling error for the Debian package build of OTB 6.6-rc2:
* Writting -> Writing
The attached patch fixes the issue: [spelling-errors.patch](/uploads/07cb28be93b2618c8d063923be8da0f3/spelling-errors.patch)
### Configuration information
OS, OTB version or tag, information related to build (binaries, superbuild, system libs ...)
issue