Add docs for DTZ005 and DTZ006 (#6529)

Changes:
- Adds docs for `DTZ005`
- Adds docs for `DTZ006`

Related to: https://github.com/astral-sh/ruff/issues/2646

crates/ruff/src/rules/flake8_datetimez/rules/call_datetime_fromtimestamp.rs

@@ -8,6 +8,44 @@ use crate::rules::flake8_datetimez::rules::helpers::has_non_none_keyword;
 
 use super::helpers;
 
+/// ## What it does
+/// Checks for usage of `datetime.datetime.fromtimestamp()` without a `tz`
+/// argument.
+///
+/// ## Why is this bad?
+/// Python datetime objects can be naive or timezone-aware. While an aware
+/// object represents a specific moment in time, a naive object does not
+/// contain enough information to unambiguously locate itself relative to other
+/// datetime objects. Since this can lead to errors, it is recommended to
+/// always use timezone-aware objects.
+///
+/// `datetime.datetime.fromtimestamp(ts)` returns a naive datetime object.
+/// Instead, use `datetime.datetime.fromtimestamp(ts, tz=)` to return a
+/// timezone-aware object.
+///
+/// ## Example
+/// ```python
+/// import datetime
+///
+/// datetime.datetime.fromtimestamp(946684800)
+/// ```
+///
+/// Use instead:
+/// ```python
+/// import datetime
+///
+/// datetime.datetime.fromtimestamp(946684800, tz=datetime.timezone.utc)
+/// ```
+///
+/// Or, for Python 3.11 and later:
+/// ```python
+/// import datetime
+///
+/// datetime.datetime.fromtimestamp(946684800, tz=datetime.UTC)
+/// ```
+///
+/// ## References
+/// - [Python documentation: Aware and Naive Objects](https://docs.python.org/3/library/datetime.html#aware-and-naive-objects)
 #[violation]
 pub struct CallDatetimeFromtimestamp;
 
@@ -20,7 +58,6 @@ impl Violation for CallDatetimeFromtimestamp {
     }
 }
 
-/// DTZ006
 pub(crate) fn call_datetime_fromtimestamp(checker: &mut Checker, call: &ast::ExprCall) {
     if !checker
         .semantic()

crates/ruff/src/rules/flake8_datetimez/rules/call_datetime_now_without_tzinfo.rs

@@ -8,6 +8,42 @@ use crate::rules::flake8_datetimez::rules::helpers::has_non_none_keyword;
 
 use super::helpers;
 
+/// ## What it does
+/// Checks for usage of `datetime.datetime.now()` without a `tz` argument.
+///
+/// ## Why is this bad?
+/// Python datetime objects can be naive or timezone-aware. While an aware
+/// object represents a specific moment in time, a naive object does not
+/// contain enough information to unambiguously locate itself relative to other
+/// datetime objects. Since this can lead to errors, it is recommended to
+/// always use timezone-aware objects.
+///
+/// `datetime.datetime.now()` returns a naive datetime object. Instead, use
+/// `datetime.datetime.now(tz=)` to return a timezone-aware object.
+///
+/// ## Example
+/// ```python
+/// import datetime
+///
+/// datetime.datetime.now()
+/// ```
+///
+/// Use instead:
+/// ```python
+/// import datetime
+///
+/// datetime.datetime.now(tz=datetime.timezone.utc)
+/// ```
+///
+/// Or, for Python 3.11 and later:
+/// ```python
+/// import datetime
+///
+/// datetime.datetime.now(tz=datetime.UTC)
+/// ```
+///
+/// ## References
+/// - [Python documentation: Aware and Naive Objects](https://docs.python.org/3/library/datetime.html#aware-and-naive-objects)
 #[violation]
 pub struct CallDatetimeNowWithoutTzinfo;
 
@@ -18,7 +54,6 @@ impl Violation for CallDatetimeNowWithoutTzinfo {
     }
 }
 
-/// DTZ005
 pub(crate) fn call_datetime_now_without_tzinfo(checker: &mut Checker, call: &ast::ExprCall) {
     if !checker
         .semantic()