Add module tag to elixir test cases (#3178)

Some elixir test cases don't have actual module tag. Add tags to
help include or exclude them in CI test.
diff --git a/test/elixir/test/update_documents_test.exs b/test/elixir/test/update_documents_test.exs
index fcbdbea..bd5e0f1 100644
--- a/test/elixir/test/update_documents_test.exs
+++ b/test/elixir/test/update_documents_test.exs
@@ -1,6 +1,7 @@
 defmodule UpdateDocumentsTest do
   use CouchTestCase
 
+  @moduletag :docs
   @moduletag kind: :single_node
 
   @ddoc %{
diff --git a/test/elixir/test/view_collation_raw_test.exs b/test/elixir/test/view_collation_raw_test.exs
index 1bcd397..b9c40f6 100644
--- a/test/elixir/test/view_collation_raw_test.exs
+++ b/test/elixir/test/view_collation_raw_test.exs
@@ -6,6 +6,7 @@
   This is a port of the view_collation_raw.js suite
   """
 
+  @moduletag :view_collation_raw
   @moduletag kind: :single_node
 
   @values [
diff --git a/test/elixir/test/view_collation_test.exs b/test/elixir/test/view_collation_test.exs
index e18e1e2..0dabd50 100644
--- a/test/elixir/test/view_collation_test.exs
+++ b/test/elixir/test/view_collation_test.exs
@@ -6,6 +6,7 @@
   This is a port of the view_collation.js suite
   """
 
+  @moduletag :view_collation
   @moduletag kind: :single_node
 
   @values [
diff --git a/test/elixir/test/view_compaction_test.exs b/test/elixir/test/view_compaction_test.exs
index 5bdd2ea..ed7461a 100644
--- a/test/elixir/test/view_compaction_test.exs
+++ b/test/elixir/test/view_compaction_test.exs
@@ -6,6 +6,7 @@
   This is a port of the view_compaction.js suite
   """
   
+  @moduletag :view_compaction
   @moduletag kind: :single_node
   
   @num_docs 1000
diff --git a/test/elixir/test/view_conflicts_test.exs b/test/elixir/test/view_conflicts_test.exs
index 9261b1e..89d9cb4 100644
--- a/test/elixir/test/view_conflicts_test.exs
+++ b/test/elixir/test/view_conflicts_test.exs
@@ -1,6 +1,7 @@
 defmodule ViewConflictsTest do
   use CouchTestCase
 
+  @moduletag :view_conflicts
   @moduletag kind: :single_node
 
   setup_all do
diff --git a/test/elixir/test/view_errors_test.exs b/test/elixir/test/view_errors_test.exs
index 80067ec..1e8f880 100644
--- a/test/elixir/test/view_errors_test.exs
+++ b/test/elixir/test/view_errors_test.exs
@@ -1,6 +1,7 @@
 defmodule ViewErrorsTest do
   use CouchTestCase
 
+  @moduletag :view_errors
   @moduletag kind: :single_node
 
   @document %{integer: 1, string: "1", array: [1, 2, 3]}
diff --git a/test/elixir/test/view_include_docs_test.exs b/test/elixir/test/view_include_docs_test.exs
index a777530..1c2ab57 100644
--- a/test/elixir/test/view_include_docs_test.exs
+++ b/test/elixir/test/view_include_docs_test.exs
@@ -1,6 +1,7 @@
 defmodule ViewIncludeDocsTest do
   use CouchTestCase
 
+  @moduletag :view_include_docs
   @moduletag kind: :single_node
 
   @ddoc %{
diff --git a/test/elixir/test/view_multi_key_all_docs_test.exs b/test/elixir/test/view_multi_key_all_docs_test.exs
index 6426eb2..c983905 100644
--- a/test/elixir/test/view_multi_key_all_docs_test.exs
+++ b/test/elixir/test/view_multi_key_all_docs_test.exs
@@ -1,6 +1,7 @@
 defmodule ViewMultiKeyAllDocsTest do
   use CouchTestCase
 
+  @moduletag :view_multi_key_all_docs
   @moduletag kind: :single_node
 
   @keys ["10", "15", "30", "37", "50"]
diff --git a/test/elixir/test/view_multi_key_design_test.exs b/test/elixir/test/view_multi_key_design_test.exs
index 1ea3fe3..03cdc57 100644
--- a/test/elixir/test/view_multi_key_design_test.exs
+++ b/test/elixir/test/view_multi_key_design_test.exs
@@ -1,6 +1,7 @@
 defmodule ViewMultiKeyDesignTest do
   use CouchTestCase
   
+  @moduletag :view_multi_key_design
   @moduletag kind: :single_node
 
   @keys [10, 15, 30, 37, 50]
diff --git a/test/elixir/test/view_sandboxing_test.exs b/test/elixir/test/view_sandboxing_test.exs
index 99a9c0d..02087ac 100644
--- a/test/elixir/test/view_sandboxing_test.exs
+++ b/test/elixir/test/view_sandboxing_test.exs
@@ -1,6 +1,7 @@
 defmodule ViewSandboxingTest do
   use CouchTestCase
 
+  @moduletag :view_sandboxing
   @moduletag kind: :single_node
 
   @document %{integer: 1, string: "1", array: [1, 2, 3]}