Fix PHP extensions not found

.devcontainer/Dockerfile

@@ -23,7 +23,6 @@ RUN set -eux; \
     libfreetype6-dev libicu-dev libjpeg62-turbo-dev \
     libpng-dev libxslt1-dev libzip-dev libwebp-dev libxml2-dev \
     ${PHP_EXTRA_BUILD_DEPS:-}; \
-    rm -rf /var/lib/apt/lists/*; \
     # https://www.php.net/manual/en/image.installation.php
     docker-php-ext-configure gd --enable-gd --with-freetype --with-jpeg --with-webp; \
     docker-php-ext-install -j$(nproc) opcache soap \
@@ -32,13 +31,14 @@ RUN set -eux; \
     apt-mark auto '.*' > /dev/null; \
     [ -z "$savedAptMark" ] || apt-mark manual $savedAptMark; \
     find /usr/local -type f -executable -exec ldd '{}' ';' \
-    | awk '/=>/ { print $(NF-1) }' \
+    | awk '/=>/ { so = $(NF-1); if (index(so, "/usr/local/") == 1) { next }; gsub("^/(usr/)?", "", so); print so }' \
     | sort -u \
     | xargs -r dpkg-query --search \
     | cut -d: -f1 \
     | sort -u \
     | xargs -r apt-mark manual; \
-    apt-get purge -y --auto-remove -o APT::AutoRemove::RecommendsImportant=false;
+    apt-get purge -y --auto-remove -o APT::AutoRemove::RecommendsImportant=false; \
+    rm -rf /var/lib/apt/lists/*;
 
 # set recommended PHP.ini settings
 # see https://secure.php.net/manual/en/opcache.installation.php