docs: fix minor typos and wording in ADRs (#8851)

Author: maradini77

adrs/001_enum_definition_syntax.md

@@ -27,7 +27,7 @@ match enum_val {
 MyEnum::Variant0(value0)
 ```
 
-This is a deviation from the rust syntax
+This is a deviation from the Rust syntax
 ```
 enum MyEnum {
     Variant0,

adrs/003_simple_trait_system.md

@@ -7,7 +7,7 @@ Accepted ?
 
 ## Context
 This suggestion introduces a basic `trait` and `impl` system.
-* It is flexible enough to allow anything that can be expressed in rust's trait system, excluding
+* It is flexible enough to allow anything that can be expressed in Rust's trait system, excluding
   dynamics.
 * It is simple, without edge cases, and hopefully easy on the compiler work.
 

docs/reference/src/components/cairo/modules/getting_started/pages/prerequisites.adoc

@@ -31,7 +31,7 @@ To set up a development environment, please follow these steps:
 . Follow the instructions in link:https://marketplace.visualstudio.com/items?itemName=starkware.cairo1[vscode-cairo].
 
 The `rustfmt` configuration used by cairo requires a nightly version of Rust.
-You can install the nightly version by running.
+You can install the nightly version by running:
 
 [source,bash]
 ----