Remove explicit working dir from dockerfiles

.pipeline/Dockerfile.build

@@ -2,7 +2,6 @@
 # precompiled dependencies.
 ARG BASE_IMAGE
 FROM $BASE_IMAGE AS build
-WORKDIR /usr/src/homepage
 
 COPY src src
 RUN cargo build --workspace --all-features --release --locked --target x86_64-unknown-linux-musl

.pipeline/Dockerfile.clippy

@@ -2,7 +2,6 @@
 # precompiled dependencies.
 ARG BASE_IMAGE
 FROM $BASE_IMAGE AS build
-WORKDIR /usr/src/homepage
 
 RUN rustup component add clippy
 

.pipeline/Dockerfile.deploy

@@ -2,7 +2,6 @@
 # precompiled dependencies.
 ARG BASE_IMAGE
 FROM $BASE_IMAGE AS build
-WORKDIR /usr/src/homepage
 
 COPY src src
 RUN cargo build --bins --release --locked --target x86_64-unknown-linux-musl
@@ -26,7 +25,7 @@ ENV HOMEPAGE_LOG_COLOR false
 EXPOSE 80/tcp
 WORKDIR /srv
 COPY --from=build \
-        /usr/src/homepage/target/x86_64-unknown-linux-musl/release/homepage \
+        /home/rust/src/target/x86_64-unknown-linux-musl/release/homepage \
         /bin/homepage
 COPY ./templates /srv/templates
 COPY ./static /srv/static

.pipeline/Dockerfile.deps

@@ -3,7 +3,6 @@
 # re-downloading dependencies if they have not changed.
 ARG BASE_IMAGE=ekidd/rust-musl-builder:stable
 FROM $BASE_IMAGE AS build
-WORKDIR /usr/src/homepage
 
 # Download the target for static linking.
 RUN rustup set profile minimal

.pipeline/Dockerfile.test

@@ -2,7 +2,6 @@
 # precompiled dependencies.
 ARG BASE_IMAGE
 FROM $BASE_IMAGE AS build
-WORKDIR /usr/src/homepage
 
 COPY src src
 RUN cargo test --workspace --all-features --release --locked --target x86_64-unknown-linux-musl