[KED-2840] Pin dynaconf to 3.1.5 (#1237)

RELEASE.md

@@ -20,6 +20,7 @@
 * Bumped minimum required `fsspec` version to 2021.04.
 * Fixed the `kedro install` and `kedro build-reqs` flows when uninstalled dependencies are present in a project's `settings.py`, `context.py` or `hooks.py` ([Issue #829](https://github.com/quantumblacklabs/kedro/issues/829)).
 * Imports are now refactored at `kedro pipeline package` and `kedro pipeline pull` time, so that _aliasing_ a modular pipeline doesn't break it.
+* Pinned `dynaconf` to `<3.1.6` because the method signature for `_validate_items` changed which is used in Kedro.
 
 ## Minor breaking changes to the API
 

docs/source/05_data/01_data_catalog.md

@@ -361,7 +361,7 @@ CSVDataSet(
 
 ## Loading multiple datasets that have similar configuration
 
-You may encounter situations where your datasets use the same file format, load and save arguments, and are stored in the same folder. YAML has a [built-in syntax](https://yaml.org/spec/1.2/#Syntax) for factorising parts of a YAML file, which means that you can decide what is generalisable across your datasets so that you do not have to spend time copying and pasting dataset configurations in `catalog.yml`.
+You may encounter situations where your datasets use the same file format, load and save arguments, and are stored in the same folder. YAML has a [built-in syntax](https://yaml.org/spec/1.2.1/#Syntax) for factorising parts of a YAML file, which means that you can decide what is generalisable across your datasets so that you do not have to spend time copying and pasting dataset configurations in `catalog.yml`.
 
 You can see this in the following example:
 

requirements.txt

@@ -2,7 +2,7 @@ anyconfig~=0.10.0
 cachetools~=4.1
 click<8.0
 cookiecutter~=1.7.0
-dynaconf~=3.1.2
+dynaconf<3.1.6 # Pinned because Dynaconf broke a method signature in 3.1.6 used in Kedro
 fsspec>=2021.04, <2022.01  # Upper bound set arbitrarily, to be reassessed in early 2022
 gitpython~=3.0
 jmespath>=0.9.5, <1.0