Update uses of LazyPath

The 'path' union field got removed upstream.

See: ziglang/zig#19826

build.zig

@@ -5,11 +5,11 @@ pub fn build(b: *std.Build) void {
  const target = b.standardTargetOptions(.{});
 
  const args_mod = b.addModule("args", .{
- .root_source_file = .{ .path = "args.zig" },
+ .root_source_file = b.path("args.zig"),
  });
 
  const main_tests = b.addTest(.{
- .root_source_file = .{ .path = "args.zig" },
+ .root_source_file = b.path("args.zig"),
  .optimize = optimize,
  .target = target,
  });
@@ -20,7 +20,7 @@ pub fn build(b: *std.Build) void {
 
  const demo_exe = b.addExecutable(.{
  .name = "demo",
- .root_source_file = .{ .path = "demo.zig" },
+ .root_source_file = b.path("demo.zig"),
  .optimize = optimize,
  .target = target,
  });
@@ -35,7 +35,7 @@ pub fn build(b: *std.Build) void {
 
  const demo_verb_exe = b.addExecutable(.{
  .name = "demo_verb",
- .root_source_file = .{ .path = "demo_verb.zig" },
+ .root_source_file = b.path("demo_verb.zig"),
  .optimize = optimize,
  .target = target,
  });