Fixes for gcc 13 (#1128)

* Add include <cstdint> where needed
* Add .devcontainer to .gitignore
* Document gcc-13 compilation fix for rocksdb

.gitignore

@@ -1,5 +1,6 @@
 *clio*.log
 /build*/
+.devcontainer
 .build
 .cache
 .vscode

README.md

@@ -86,6 +86,8 @@ conan remote add --insert 0 conan-non-prod http://18.143.149.228:8081/artifactor
 ```
 Now you should be able to download prebuilt `xrpl` package on some platforms.
 
+You might need to edit the `~/.conan/remotes.json` file to ensure that this newly added artifactory is listed last. Otherwise you might see compilation errors when building the project with gcc version 13 (or newer).
+
 2. Remove old packages you may have cached: 
 ```sh 
 conan remove -f xrpl

src/util/config/detail/Helpers.h

@@ -19,6 +19,7 @@
 
 #pragma once
 
+#include <cstdint>
 #include <optional>
 #include <queue>
 #include <stdexcept>

src/util/prometheus/MetricBase.h

@@ -22,6 +22,8 @@
 #include "util/prometheus/Label.h"
 #include "util/prometheus/OStream.h"
 
+#include <cstdint>
+
 namespace util::prometheus {
 
 /**