refactor(ng-dev/release): centralize and expand ignored paths for snapshot publishing

Centralizes the paths to exclude when detecting changes for snapshot
publishing into a single constant. Additionally, adds `pubspec.lock`
to the list of ignored files to avoid unnecessary snapshot releases
when only lock files change.

Author: alan-agius4

ng-dev/release/snapshot-publish/snapshots.ts

@@ -31,6 +31,11 @@ interface SnapshotRepo {
   containsChanges: boolean;
 }
 
+/**
+ * Paths to exclude from the snapshot commit.
+ */
+const PATHS_TO_EXCLUDE = ['**/MODULE.bazel.lock', '**/package-lock.json', '**/pubspec.lock'];
+
 export class SnapshotPublisher {
   /** The current branch name. */
   readonly branchName = this.git.getCurrentBranchOrRevision();
@@ -166,8 +171,7 @@ export class SnapshotPublisher {
               'HEAD',
               '--',
               '.',
-              ':(exclude)**/MODULE.bazel.lock',
-              ':(exclude)**/package-lock.json',
+              ...PATHS_TO_EXCLUDE.map((p) => `:(exclude)${p}`),
             ],
             {cwd: tmpRepoDir},
           ).status === 1;