Require Rust 1.62 for enum defaults

All our examples use codegen from `graphql_client_codegen` which
uses [enum defaults][1] which are only [supported as of 1.62][2].

This commit makes that requirement explicit for a more helpful error
message:

> $ cargo build
> error: package [..] ([.. path..]])` cannot be built because it
> requires rustc 1.62.0 or newer, while the currently active rustc
> version is 1.61.0

[1]: https://github.com/graphql-rust/graphql-client/blob/33b8a34aabbaaac9977a93763ae445dc64b5c67c/graphql_client_codegen/src/deprecation.rs#L10-L20
[2]: rust-lang/rust#94457 (comment)

Author: jbourassa

checkout/rust/cart-transform/bundles/Cargo.toml.liquid

@@ -2,6 +2,7 @@
 name = "bundles_cart_transform"
 version = "1.0.0"
 edition = "2021"
+rust-version = "1.62"
 
 [dependencies]
 serde = { version = "1.0.13", features = ["derive"] }

checkout/rust/delivery-customization/default/Cargo.toml.liquid

@@ -2,6 +2,7 @@
 name = "{{name | replace: " ", "-" | downcase}}"
 version = "1.0.0"
 edition = "2021"
+rust-version = "1.62"
 
 [dependencies]
 serde = { version = "1.0.13", features = ["derive"] }

discounts/rust/order-discounts/default/Cargo.toml.liquid

@@ -2,6 +2,7 @@
 name = "{{name | replace: " ", "-" | downcase}}"
 version = "1.0.0"
 edition = "2021"
+rust-version = "1.62"
 
 [dependencies]
 serde = { version = "1.0.13", features = ["derive"] }

discounts/rust/product-discounts/default/Cargo.toml.liquid

@@ -2,6 +2,7 @@
 name = "{{name | replace: " ", "-" | downcase}}"
 version = "1.0.0"
 edition = "2021"
+rust-version = "1.62"
 
 [dependencies]
 serde = { version = "1.0.13", features = ["derive"] }

discounts/rust/shipping-discounts/default/Cargo.toml.liquid

@@ -2,6 +2,7 @@
 name = "{{name | replace: " ", "-" | downcase}}"
 version = "1.0.0"
 edition = "2021"
+rust-version = "1.62"
 
 [dependencies]
 serde = { version = "1.0.13", features = ["derive"] }

order-routing/rust/fulfillment-constraints/default/Cargo.toml.liquid

@@ -2,6 +2,7 @@
 name = "{{name | replace: " ", "-" | downcase}}"
 version = "1.0.0"
 edition = "2021"
+rust-version = "1.62"
 
 [dependencies]
 serde = { version = "1.0.13", features = ["derive"] }

order-routing/rust/rankers/default/Cargo.toml.liquid

@@ -2,6 +2,7 @@
 name = "{{name | replace: " ", "-" | downcase}}"
 version = "1.0.0"
 edition = "2021"
+rust-version = "1.62"
 
 [dependencies]
 serde = { version = "1.0.13", features = ["derive"] }

sample-apps/bundles-cart-transform/extensions/cart-merge-expand/Cargo.toml

@@ -2,6 +2,7 @@
 name = "bundle_cart_transform"
 version = "1.0.0"
 edition = "2021"
+rust-version = "1.62"
 
 [dependencies]
 serde = { version = "1.0.13", features = ["derive"] }

sample-apps/delivery-customizations/extensions/delivery-customization-rust/Cargo.toml

@@ -2,6 +2,7 @@
 name = "delivery-customization"
 version = "1.0.0"
 edition = "2021"
+rust-version = "1.62"
 
 [dependencies]
 serde = { version = "1.0.13", features = ["derive"] }

sample-apps/discounts/extensions/product-discount-rust/Cargo.toml

@@ -2,6 +2,7 @@
 name = "product-discount"
 version = "1.0.0"
 edition = "2021"
+rust-version = "1.62"
 
 [dependencies]
 serde = { version = "1.0.13", features = ["derive"] }

sample-apps/payment-customizations/extensions/payment-customization-rust/Cargo.toml

@@ -2,6 +2,7 @@
 name = "payment-customization"
 version = "1.0.0"
 edition = "2021"
+rust-version = "1.62"
 
 [dependencies]
 serde = { version = "1.0.13", features = ["derive"] }