Remove some URL references from the documentation.

These were to methods in the primitive type `str`, so the references resolve correctly on their own.

PiperOrigin-RevId: 527812163

Author: hovinenb

googletest/src/matchers/str_matcher.rs

@@ -157,8 +157,6 @@ pub trait StrMatcherConfigurator<ExpectedT> {
     /// When all other configuration options are left as the defaults, this is
     /// equivalent to invoking [`str::trim_start`] on both the expected and
     /// actual value.
-    ///
-    /// [`str::trim_start`]: https://doc.rust-lang.org/std/primitive.str.html#method.trim_start
     fn ignoring_leading_whitespace(self) -> StrMatcher<ExpectedT>;
 
     /// Configures the matcher to ignore any trailing whitespace in either the
@@ -181,8 +179,6 @@ pub trait StrMatcherConfigurator<ExpectedT> {
     /// When all other configuration options are left as the defaults, this is
     /// equivalent to invoking [`str::trim_end`] on both the expected and
     /// actual value.
-    ///
-    /// [`str::trim_end`]: https://doc.rust-lang.org/std/primitive.str.html#method.trim_end
     fn ignoring_trailing_whitespace(self) -> StrMatcher<ExpectedT>;
 
     /// Configures the matcher to ignore both leading and trailing whitespace in
@@ -209,8 +205,6 @@ pub trait StrMatcherConfigurator<ExpectedT> {
     /// When all other configuration options are left as the defaults, this is
     /// equivalent to invoking [`str::trim`] on both the expected and actual
     /// value.
-    ///
-    /// [`str::trim`]: https://doc.rust-lang.org/std/primitive.str.html#method.trim
     fn ignoring_outer_whitespace(self) -> StrMatcher<ExpectedT>;
 
     /// Configures the matcher to ignore ASCII case when comparing values.
@@ -235,8 +229,6 @@ pub trait StrMatcherConfigurator<ExpectedT> {
     ///
     /// This is **not guaranteed** to match strings with differing upper/lower
     /// case characters outside of the codepoints 0-127 covered by ASCII.
-    ///
-    /// [`str::eq_ignore_ascii_case`]: https://doc.rust-lang.org/std/primitive.str.html#method.eq_ignore_ascii_case
     fn ignoring_ascii_case(self) -> StrMatcher<ExpectedT>;
 
     /// Configures the matcher to match only strings which otherwise satisfy the