Fix couple of code blocks, doc paths in docgen templates.

* Replace ```shell with ```sh to fix jekyll build errors
* Fix paths in docgen templates for new docs site directory structure.
* Add jekyll build output directories to gitignore.

RELNOTES: None
PiperOrigin-RevId: 159020213
diff --git a/site/docs/tutorial/cpp.md b/site/docs/tutorial/cpp.md
index dbf90f5..e0a5e70 100644
--- a/site/docs/tutorial/cpp.md
+++ b/site/docs/tutorial/cpp.md
@@ -152,7 +152,7 @@
 
 Now test your freshly built binary:
 
-```shell
+```sh
 bazel-bin/main/hello-world
 ```
 
diff --git a/site/docs/tutorial/java.md b/site/docs/tutorial/java.md
index 4a80d47..34cb7b5 100644
--- a/site/docs/tutorial/java.md
+++ b/site/docs/tutorial/java.md
@@ -29,7 +29,7 @@
 you don't have it installed already. Then, retrieve the sample project from
 Bazel's GitHub repository:
 
-```
+```sh
 git clone https://github.com/bazelbuild/examples/
 ```
 
@@ -134,7 +134,7 @@
 
 Now test your freshly built binary:
 
-```shell
+```sh
 bazel-bin/ProjectRunner
 ```