Add *.rst to list of files to include from test prefix

This merge request add the .rst files from the test prefix to the package.

They will be used in tests of other packages like beat/beat.editor>

A new algorithm has been created for missing documentation related tests.

beat/backend/python/test/prefix/algorithms/legacy/no_doc/1.json

+{
+    "language": "python",
+    "splittable": false,
+    "parameters": {
+        "sync": {
+            "default": "in1",
+            "type": "string"
+        }
+    },
+    "groups": [
+        {
+            "inputs": {
+                "in1": {
+                    "type": "user/single_integer/1"
+                },
+                "in2": {
+                    "type": "user/single_integer/1"
+                }
+            },
+            "outputs": {
+                "out": {
+                    "type": "user/single_integer/1"
+                }
+            }
+        }
+    ]
+}