chore: fix kokoro config for samples (#85)

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Author: yoshi-automation

.kokoro/samples/python3.6/periodic-head.cfg

@@ -7,5 +7,5 @@ env_vars: {
 
 env_vars: {
     key: "TRAMPOLINE_BUILD_FILE"
-    value: "github/python-pubsub/.kokoro/test-samples-against-head.sh"
+    value: "github/python-compute/.kokoro/test-samples-against-head.sh"
 }

.kokoro/samples/python3.7/periodic-head.cfg

@@ -7,5 +7,5 @@ env_vars: {
 
 env_vars: {
     key: "TRAMPOLINE_BUILD_FILE"
-    value: "github/python-pubsub/.kokoro/test-samples-against-head.sh"
+    value: "github/python-compute/.kokoro/test-samples-against-head.sh"
 }

.kokoro/samples/python3.8/periodic-head.cfg

@@ -7,5 +7,5 @@ env_vars: {
 
 env_vars: {
     key: "TRAMPOLINE_BUILD_FILE"
-    value: "github/python-pubsub/.kokoro/test-samples-against-head.sh"
+    value: "github/python-compute/.kokoro/test-samples-against-head.sh"
 }

.kokoro/samples/python3.9/periodic-head.cfg

@@ -7,5 +7,5 @@ env_vars: {
 
 env_vars: {
     key: "TRAMPOLINE_BUILD_FILE"
-    value: "github/python-pubsub/.kokoro/test-samples-against-head.sh"
+    value: "github/python-compute/.kokoro/test-samples-against-head.sh"
 }

synth.metadata

@@ -4,7 +4,7 @@
       "git": {
         "name": ".",
         "remote": "https://github.com/googleapis/python-compute.git",
-        "sha": "1163f2bb15f0e042bdd9562a31ad2ac7f39e3536"
+        "sha": "40afb333a963717853f70410a7a08eda5492418c"
       }
     },
     {