Fix -B --noconfirm conflict check

[gyscos]

As reported in #1376, trying to build a package that would conflict with any installed packages currently works interactively, but not with --noconfirm.

7799203 was trying to fix the problem, but the issue persists on the latest master.

To reproduce, an easy way is trying to build one of paru/paru-bin/paru-git (whichever is not currently installed on the system, or all 3).

Example if paru is already installed, trying to build paru-bin:

cargo run -- -G paru-bin && cargo run -- -B --noconfirm paru-bin

Currently on the latest master, this outputs:

:: Generating .SRCINFO for ./paru-bin...
:: Resolving dependencies...
:: Calculating conflicts...
:: Calculating inner conflicts...

:: Conflicts found:
    paru-bin: paru

:: Conflicting packages will have to be confirmed manually
error: can not install conflicting packages with --noconfirm

Another reproduction example: the eternalterminal package. It's a split package with 3 packages: a client, a server, and a package that includes both (unfortunately not a virtual package that depends on both the client and the server). Trying to build it produces internal conflicts with the current master branch, but works with this PR.

cargo run -- -G eternalterminal && cargo run -- -B --noconfirm eternalterminal

In this branch, this properly builds the package.

This now:

• Properly accounts for all packages being built, not just the latest one (for split packages where we build multiple packages)
• Apply the filter on inner conflicts as well, which is what was being triggered on no-confirm.

[pfeifferj]

testdata/clone/devel-bin/ is missing its .SRCINFO. Mock::new() walks every subdir of testdata/clone/ and does Srcinfo::from_path(dir.path().join(".SRCINFO"))? on startup, so with just a PKGBUILD it ENOENTs and every test panics before running. that's why ci is red

[gyscos]

Aaah I see, was trying to figure out what I broke :)

Will fix that, thanks!