Remove rich from required dependencies (streamlit#10320)

## Describe your changes

We have a Python dependency in Streamlit - `rich` - that is almost
exclusively used in Community Cloud to get nicer formatting for
exceptions in the log viewer. However, it is currently installed for all
Streamlit installs, which is suboptimal. The dependency is already
implemented in Streamlit in a way that it is optional (only used if
installed). We have recently changed that `rich` gets auto-installed on
Community Cloud, therefore, we can remove it from Streamlit's required
dependencies.

In a follow-up after the release, we also plan to deprecate and
eventually remove the `logger.enableRich` config option and always use
`rich` if installed.

## Testing Plan

- No logical changes. Rich is already an optional dependency in the code
logic.

---

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Author: lukasmasuch

lib/min-constraints-gen.txt

@@ -11,7 +11,6 @@ protobuf==3.20
 pyarrow==7.0
 pydeck==0.8.0b4
 requests==2.27
-rich==10.14.0
 tenacity==8.1.0
 toml==0.10.1
 tornado==6.0.3

lib/setup.py

@@ -46,7 +46,6 @@
     # upper bound on it.
     "pyarrow>=7.0",
     "requests>=2.27, <3",
-    "rich>=10.14.0, <14",
     "tenacity>=8.1.0, <10",
     "toml>=0.10.1, <2",
     "typing-extensions>=4.4.0, <5",

lib/streamlit/config.py

@@ -474,8 +474,9 @@ def _logger_message_format() -> str:
     description="""
         Controls whether uncaught app exceptions are logged via the rich library.
 
-        If True and if rich is installed, exception tracebacks will be logged with syntax highlighting and formatting.
-        Rich tracebacks are easier to read and show more code than standard Python tracebacks.
+        If True and if rich is installed, exception tracebacks will be logged with
+        syntax highlighting and formatting. Rich tracebacks are easier to read and
+        show more code than standard Python tracebacks.
 
         If set to False, the default Python traceback formatting will be used.
     """,

lib/test-requirements.txt

@@ -8,6 +8,10 @@ matplotlib>=3.3.4
 plotly>=5.3.1
 seaborn>=0.11.2
 watchdog>=2.1.5
+# Optional dependency used for improved exception formatting
+# in Community Cloud:
+rich>=10.14.0
+
 # We still need numpy < 2 for our bokeh tests since
 # bokeh 2.4.3 is incompatible with numpy 2.x:
 numpy<2