Adopt absl::string_view in function parameters under rtc_base/

This is part of a large-scale effort to increase adoption of
absl::string_view across the WebRTC code base.

This CL converts the majority of "const std::string&"s in function
parameters under rtc_base/ to absl::string_view.

Bug: webrtc:13579
Change-Id: I2b1e3776aa42326aa405f76bb324a2d233b21dca
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/254081
Reviewed-by: Niels Moller <nisse@webrtc.org>
Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
Reviewed-by: Xavier Lepaul‎ <xalep@webrtc.org>
Reviewed-by: Anders Lilienthal <andersc@webrtc.org>
Reviewed-by: Per Kjellander <perkj@webrtc.org>
Commit-Queue: Ali Tofigh <alito@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#36239}

rtc_base/strings/string_builder.h

@@ -32,9 +32,8 @@ class SimpleStringBuilder {
   SimpleStringBuilder(const SimpleStringBuilder&) = delete;
   SimpleStringBuilder& operator=(const SimpleStringBuilder&) = delete;
 
-  SimpleStringBuilder& operator<<(const char* str);
   SimpleStringBuilder& operator<<(char ch);
-  SimpleStringBuilder& operator<<(const std::string& str);
+  SimpleStringBuilder& operator<<(absl::string_view str);
   SimpleStringBuilder& operator<<(int i);
   SimpleStringBuilder& operator<<(unsigned i);
   SimpleStringBuilder& operator<<(long i);                // NOLINT