pw_containers: Remove static max_size() function

Remove the static version of max_size() for consistency with std::vector
and std::array and to avoid potentially reporting inaccurate values in
unusual situations such as working with aliased types.

Change-Id: I5647ab7e882b65c09b8d616a81835c92b85d8abb
diff --git a/pw_containers/public/pw_containers/vector.h b/pw_containers/public/pw_containers/vector.h
index 57f5321..a518f28 100644
--- a/pw_containers/public/pw_containers/vector.h
+++ b/pw_containers/public/pw_containers/vector.h
@@ -112,8 +112,6 @@
     return *this;
   }
 
-  static constexpr size_type max_size() noexcept { return kMaxSize; }
-
   // All other vector methods are implemented on the Vector<T> base class.
 
  private:
@@ -241,6 +239,8 @@
 
   [[nodiscard]] bool empty() const noexcept { return size() == 0u; }
 
+  // True if there is no free space in the vector. Operations that add elements
+  // (push_back, insert, etc.) will fail if full() is true.
   [[nodiscard]] bool full() const noexcept { return size() == max_size(); }
 
   size_type size() const noexcept { return size_; }