Fix typo in html text.

README.md

@@ -71,7 +71,7 @@ Open **Anaconda Prompt** or a terminal with access to conda.
    ```
 
 <details> 
-<summary> <h3> Working with Jupyter Notebooks </h3> </summary>
+<summary> <b> Working with Jupyter Notebooks </b> </summary>
 
 We now make the previously installed Python environment `multiphase_chemistry_env` selectable as a kernel in Jupyter's interface.
 
@@ -167,12 +167,18 @@ If you have run out of energy or time for your project, put a note at the top of
 ## How-to tutorials
 
 <details> 
-<summary> <h3> Data integration workflow </h3>
-<details>
+
+<summary> <b> Data integration workflow </b> </summary>
+
+This section is in progress!
+
+</details>
 
 
 <details> 
-<summary> <h3> Metadata review workflow </h3>
+
+<summary> <b> Metadata review workflow </b> </summary>
+
 - review through branches
 - updating files with metadata in Openbis
 
@@ -224,7 +230,7 @@ relative_humidity:
   definition: 'Relative humidity represents the amount of water vapor present in the air relative to the maximum amount of water vapor the air can hold at a given temperature.'
 
 ```
-<details>
+</details>
 
 # Editing this README