Remove prerequisites from tutorial (#2009)

And add a note on Plotly.
Fixes #1998
Fixes #1997
Fixes #2001

Author: visr

docs/tutorial/irrigation-demand.ipynb

@@ -162,7 +162,7 @@
     "An irrigation district needs to apply irrigation to its field starting from April to September.\n",
     "The irrigated area is $> 17000 \\text{ ha}$ and requires around $5 \\text{ mm/day}$.\n",
     "In this case the irrigation district diverts from the main river an average flow rate of $10 \\text{ m}^3/\\text{s}$ and $12 \\text{ m}^3/\\text{s}$ during spring and summer, respectively.\n",
-    "Start of irrigation takes place on the 1st of April until the end of August.\n",
+    "Start of irrigation takes place on the 1st of April until the end of September.\n",
     "The water intake is through a canal (demand).\n",
     "\n",
     "For now, let's assume the return flow remains $0.0$ (`return_factor`).\n",

docs/tutorial/natural-flow.ipynb

@@ -20,6 +20,9 @@
     "The Ribasim Python package (named `ribasim`) simplifies the process of building, updating, and analyzing Ribasim model programmatically.\n",
     "It also allows for the creation of entire models from base data, ensuring that your model setup is fully reproducible.\n",
     "\n",
+    "To run this tutorial locally, install the latest release of Ribasim as documented in [the installation guide](/install.qmd).\n",
+    "Some of the tutorials use a Python package that must be installed separately, [Plotly](https://plotly.com/python/getting-started/#installation).\n",
+    "\n",
     "## Learning objectives\n",
     "In this tutorial, we will focus on a fictional river basin called Crystal, which will serve as our case study.\n",
     "The guide is divided into different modules, each covering various scenarios.\n",
@@ -30,16 +33,7 @@
     "- **Set up a basic Ribasim model**: Understand how to create a new model for a river basin using the Ribasim Python package.\n",
     "- **Evaluate the impact of demands**: Introduce water demand (such as irrigation) and assess their effects on the river basin.\n",
     "- **Modify and update models**: Learn how to update existing models with new data and changes.\n",
-    "- **Analyze simulation results**: Use built-in tools to analyze and interpret the results of your simulations.\n",
-    "\n",
-    "## Prerequisites\n",
-    "First install the latest release of Ribasim as documented in [the installation guide](/install.qmd).\n",
-    "\n",
-    "Download the `Crystal_Basin.zip` file from the website. Extract `Crystal_Basin.zip` and place it in the same directory as your Ribasim installation. This folder includes:\n",
-    "\n",
-    "- `QuickStartGuide.pdf`\n",
-    "- `data`: Contains data inputs such as time series needed for running the case.\n",
-    "Additionally, your Python model (`.py`) and the results will also be saved in this folder."
+    "- **Analyze simulation results**: Use built-in tools to analyze and interpret the results of your simulations."
    ]
   },
   {