Error E0658 when building on Arch Linux #26

I recieved the following error when running cargo build, with cargo version 1.53.0 and rustc 1.53.0:

Compiling tangram_table v0.6.0 (/usr/src/tangram/crates/table)
Compiling hyper v0.14.9
Compiling tracing-wasm v0.2.0
Compiling aws-creds v0.26.0
Compiling wasm-bindgen-cli-support v0.2.74
Compiling tangram_license v0.0.0 (/usr/src/tangram/crates/license)
Compiling tangram_features v0.6.0 (/usr/src/tangram/crates/features)
Compiling tangram_tree v0.6.0 (/usr/src/tangram/crates/tree)
Compiling web-sys v0.3.51
Compiling wasm-bindgen-futures v0.4.24
Compiling serde-wasm-bindgen v0.3.0
Compiling sunfish v0.2.5
Compiling hyper-rustls v0.22.1
Compiling tangram_linear v0.6.0 (/usr/src/tangram/crates/linear)
error[E0658]: arbitrary expressions in key-value attributes are unstable
--> crates/linear/lib.rs:1:10
|
1 | #![doc = include_str!("./README.md")]
| ^^^^^^^^^^^^^^^^^^^^^^^^^^^
|
= note: see issue #78835 rust-lang/rust#78835 for more information

error: aborting due to previous error

For more information about this error, try
rustc --explain E0658.
error: could not compile tangram_linear

To learn more, run the command again with --verbose.
warning: build failed, waiting for other jobs to finish...
error: build failed