perf(turbopack): Do not inline synthesized content for sourcemaps (#79173)
### What?
Disable `inline_sources_content` of SWC source map generator for `minify()`.
### Why?
Regardless, it's the wrong value from the user's perspective, so we cannot use it anyway.
build_sourcemap will fill the sourcemap with the content provided by the value passed to cm.new_source_file at
https://github.com/vercel/next.js/blob/bcd799fc688fc3b1535150e24c6057033e29bf3c/turbopack/crates/turbopack-ecmascript/src/minify.rs#L41-L44
but for minify(), it's not the input string (written by the user) but it's a codegen-ed string.
Also, `sourcemap::SourceMap::adjust_mappings` says
> /// This function assumes that `adjustment` contains no relevant
information except for mappings.
> /// All information about sources and names is copied from `self`.
so we do not need inline source contents regardless if we are going to call it.