Require libsoup-3.0 in meson.build
Commit 370d375d ported lollypop to libsoup-3.0 but meson.build
was still requiring libsoup-2.4.
Fixes #2959 (closed).
Commit 370d375d ported lollypop to libsoup-3.0 but meson.build
was still requiring libsoup-2.4.
Fixes #2959 (closed).