Enable BLS portable feature on all CI tests (#4868)

## Issue Addressed

Addresses the recent CI failures caused by caching `blst` for the wrong CPU type. 

## Proposed Changes

- Use `FEATURES: jemalloc,portable` when building Lighthouse & `lcli` in tests
- Add a new `TEST_FEATURES` and set to `portable` for all CI test jobs.
- Updated Makefiles to read the `TEST_FEATURES` environment variable, and default to none.

testing/ef_tests/Cargo.toml

@@ -9,6 +9,7 @@ edition = { workspace = true }
 ef_tests = []
 milagro = ["bls/milagro"]
 fake_crypto = ["bls/fake_crypto"]
+portable = ["beacon_chain/portable"]
 
 [dependencies]
 bls = { workspace = true }

testing/execution_engine_integration/Cargo.toml

@@ -22,3 +22,6 @@ reqwest = { workspace = true }
 hex = { workspace = true }
 fork_choice = { workspace = true }
 logging = { workspace = true }
+
+[features]
+portable = ["types/portable"]

testing/execution_engine_integration/Makefile

@@ -1,5 +1,5 @@
 test:
-	cargo run --release --locked
+	cargo run --release --locked --features "$(TEST_FEATURES)"
 
 clean:
 	rm -rf execution_clients

testing/state_transition_vectors/Cargo.toml

@@ -13,3 +13,6 @@ ethereum_ssz = { workspace = true }
 beacon_chain = { workspace = true }
 lazy_static = { workspace = true }
 tokio = { workspace = true }
+
+[features]
+portable = ["beacon_chain/portable"]

testing/state_transition_vectors/Makefile

@@ -2,7 +2,7 @@ produce-vectors:
 	cargo run --release
 
 test:
-	cargo test --release
+	cargo test --release --features "$(TEST_FEATURES)"
 
 clean:
 	rm -r vectors/