bep/imagemeta allows a potentially large memory allocation in PNG and WebP parsing

bep/imagemeta is a Go library for reading EXIF, IPTC and XMP image meta data from JPEG, TIFF, PNG, and WebP files. The buffer created for parsing metadata for PNG and WebP images was only bounded by their input data type, which could lead to potentially large memory allocation, and unreasonably high for image metadata. Before v0.11.0, If you didn't trust the input images, this could be abused to construct denial-of-service attacks. v0.11.0 added a 10 MB upper limit.