Commit Message: add abi.h to go mod vendor tree
Additional Description: go mod vendor is a common way in Golang to import modules/packages. It works by downloading and storing the locked version of a dependency in a vendor directory within the module. Vendoring skips downloading and storing all directories that do not have Go source files. This is a problem because the Go dynamic modules SDK uses a CGO preamble with an import of this header file, but this header is missing from the vendor download. This change adds a dummy Go file that will make Go treat this directory as a valid Go package and thus let it be imported so the header will exist properly.

Risk Level: none
Testing: n/a
Docs Changes: n/a
Release Notes: n/a
Platform Specific Features: n/a

Request variables

Key	Value
ref	2e93432
sha	0696a7b
pr	44395
base-sha	0fdd3b1
actor	@AdamEAnderson
message	dynamic modules: add abi.h to go mod vendor tree...
started	1775863998.999734
target-branch	main
trusted	false

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