hotfix/user guide job example (#88)

Author: mingkang111

docs/requirements.txt

@@ -1,4 +1,3 @@
--e .
 autodoc
 nbsphinx
 sphinx

docs/source/user_guide/jobs/run_script.rst

@@ -128,6 +128,10 @@ This example runs a job with CLI arguments:
 
 .. code-block:: python3
 
+  from ads.jobs import Job
+  from ads.jobs import DataScienceJob
+  from ads.jobs import ScriptRuntime
+
   job = Job()
   job.with_infrastructure(
     DataScienceJob()
@@ -161,9 +165,9 @@ You could create the preceding example job with the following YAML file:
 
 .. code-block:: yaml
 
-	kind: job
-	spec:
-	  infrastructure:
+  kind: job
+  spec:
+    infrastructure:
       kind: infrastructure
       type: dataScienceJob
       spec:
@@ -177,14 +181,14 @@ You could create the preceding example job with the following YAML file:
           memoryInGBs: 16
           ocpus: 1
         blockStorageSize: 50
-	  runtime:
-	    kind: runtime
+    runtime:
+      kind: runtime
       type: python
-	    spec:
-	      args:
-	      - <first_argument>
-	      - <second_argument>
-	      scriptPathURI: job_script_argument.py
+      spec:
+        args:
+        - <first_argument>
+        - <second_argument>
+      scriptPathURI: job_script_env.py
 
 
 Environment Variables
@@ -201,12 +205,16 @@ Suppose you want to run the following python script named ``job_script_env.py``:
 
   import os
   import sys
-  print("Hello " + os.environ["KEY1"] + " and " + os.environ["KEY2"])""")
+  print("Hello " + os.environ["KEY1"] + " and " + os.environ["KEY2"])
 
 This example runs a job with environment variables:
 
 .. code-block:: python3
 
+  from ads.jobs import Job
+  from ads.jobs import DataScienceJob
+  from ads.jobs import ScriptRuntime
+
   job = Job()
   job.with_infrastructure(
     DataScienceJob()
@@ -246,12 +254,12 @@ You could create the preceding example job with the following YAML file:
 
 .. code-block:: yaml
 
-	kind: job
-	spec:
-	  infrastructure:
-	    kind: infrastructure
+  kind: job
+  spec:
+    infrastructure:
+      kind: infrastructure
       type: dataScienceJob
-	    spec:
+      spec:
         logGroupId: <log_group_ocid>
         logId: <log_ocid>
         compartmentId: <compartment_ocid>
@@ -262,16 +270,16 @@ You could create the preceding example job with the following YAML file:
           memoryInGBs: 16
           ocpus: 1
         blockStorageSize: 50
-	  runtime:
-	    kind: runtime
+    runtime:
+      kind: runtime
       type: python
-	    spec:
-	      env:
-	      - name: KEY1
-	        value: <first_value>
-	      - name: KEY2
-		      value: <second_value>
-	      scriptPathURI: job_script_env.py
+      spec:
+        env:
+        - name: KEY1
+          value: <first_value>
+        - name: KEY2
+          value: <second_value>
+      scriptPathURI: job_script_env.py