Working directory is hardcoded in StableDiffusionAITPipeline and StableDiffusionImg2ImgAITPipeline in examples

[dhawalkp]

Issue: StableDiffusionAITPipeline and StableDiffusionImg2ImgAITPipeline in pipeline_stable_diffusion_ait.py and [pipeline_stable_diffusion_img2img_ait.py has workdir hardcoded to "tmp/" which might create problems where the file system locations are either read-only or users have restricted permissions in the current working directory. Examples include managed ML services in Cloud that might have file permission restrictions.

Desired behavior: User should be given flexibility to specify the custom location as workdir where AITemplate .so files are downloaded.

Files that needs a configurable workdir are below : https://github.com/facebookincubator/AITemplate/blob/262815bcf2bf76cc1addfc0fdbd555fccfba1689/examples/05_stable_diffusion/src/pipeline_stable_diffusion_img2img_ait.py#L112 https://github.com/facebookincubator/AITemplate/blob/262815bcf2bf76cc1addfc0fdbd555fccfba1689/examples/05_stable_diffusion/src/pipeline_stable_diffusion_ait.py#L101