[jnigen] Add paths to github workflow

.github/workflows/jnigen.yaml

diff --git a/.github/workflows/jnigen.yaml b/.github/workflows/jnigen.yaml
index deba348..2deae7f 100644
--- a/.github/workflows/jnigen.yaml
+++ b/.github/workflows/jnigen.yaml
@@ -13,8 +13,16 @@
   # Run on PRs and pushes to the default branch.
   push:
     branches: [main]
+    paths:
+      - '.github/workflows/jnigen.yaml'
+      - 'pkgs/jnigen/**'
+      - 'pkgs/jni/**'
   pull_request:
     branches: [main]
+    paths:
+      - '.github/workflows/jnigen.yaml'
+      - 'pkgs/jnigen/**'
+      - 'pkgs/jni/**'
   schedule:
     - cron: '0 0 * * 0'