feat(land): allow empty commits with fixupAll (#681)

Author: aduh95

lib/landing_session.js

@@ -116,10 +116,12 @@ export default class LandingSession extends Session {
     const commitInfo = { base, head, shas: commitShas };
     this.saveCommitInfo(commitInfo);
 
+    const allowEmptyCommits = this.fixupAll ? ['--allow-empty'] : [];
     try {
-      await forceRunAsync('git', ['cherry-pick', `${base}..${head}`], {
-        ignoreFailure: false
-      });
+      await forceRunAsync('git',
+        ['cherry-pick', ...allowEmptyCommits, `${base}..${head}`],
+        { ignoreFailure: false }
+      );
     } catch (ex) {
       cli.error('Failed to apply patches');
       process.exit(1);